Error loading C4 realnewslike dataset
@bhavitvyamalik @lhoestq , just tried the above and got:
>>> a=datasets.load_dataset('c4','en.realnewslike')
Downloading: 3.29kB [00:00, 1.66MB/s]                                                                                                                                                                                                                                          
Downloading: 2.40MB [00:00, 12.6MB/s]                                                                                                                                                                                                                                          
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/load.py", line 819, in load_dataset
    builder_instance = load_dataset_builder(
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/load.py", line 701, in load_dataset_builder
    builder_instance: DatasetBuilder = builder_cls(
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 1049, in __init__
    super(GeneratorBasedBuilder, self).__init__(*args, **kwargs)
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 268, in __init__
    self.config, self.config_id = self._create_builder_config(
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 360, in _create_builder_config
    raise ValueError(
ValueError: BuilderConfig en.realnewslike not found. Available: ['en', 'realnewslike', 'en.noblocklist', 'en.noclean']
>>> 

datasets version is 1.11.0

## Describe the bug
Error loading C4 realnewslike dataset. Validation part mismatch

## Steps to reproduce the bug
```python
 raw_datasets = load_dataset('c4', 'realnewslike', cache_dir=model_args.cache_dir)
## Expected results
success on data loading
## Actual results
Downloading: 100%|████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████| 15.3M/15.3M [00:00<00:00, 28.1MB/s]Traceback (most recent call last):                                                                                                                                                                                                                                             
  File "run_mlm_tf.py", line 794, in <module>                                                                                                                                                                                                                                  
    main()                                                                                                                                                                                                                                                                     
  File "run_mlm_tf.py", line 425, in main                                                                                                                                                                                                                                      
    raw_datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name, cache_dir=model_args.cache_dir)                                                                                                                                                           File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/load.py", line 843, in load_dataset                                                                                                                                                                         
    builder_instance.download_and_prepare(                                                                                                                                                                                                                                     
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 608, in download_and_prepare                                                                                                                                                              
    self._download_and_prepare(                                                                                                                                                                                                                                                
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 698, in _download_and_prepare                                                                                                                                                                 verify_splits(self.info.splits, split_dict)                                                                                                                                                                                                                                  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/utils/info_utils.py", line 74, in verify_splits                                                                                                                                                             
    raise NonMatchingSplitsSizesError(str(bad_splits))                                                                                                                                                                                                                         
datasets.utils.info_utils.NonMatchingSplitsSizesError: [{'expected': SplitInfo(name='validation', num_bytes=38165657946, num_examples=13799838, dataset_name='c4'), 'recorded': SplitInfo(name='validation', num_bytes=37875873, num_examples=13863, dataset_name='c4')}] 

## Environment info
- `datasets` version: 1.10.2
- Platform: Linux-5.4.0-58-generic-x86_64-with-glibc2.29
- Python version: 3.8.10
- PyArrow version: 4.0.1
Error loading C4 realnewslike dataset 
 ## Describe the bug
Error loading C4 realnewslike dataset. Validation part mismatch

## Steps to reproduce the bug
```python
 raw_datasets = load_dataset('c4', 'realnewslike', cache_dir=model_args.cache_dir)
## Expected results
success on data loading
## Actual results
Downloading: 100%|████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████| 15.3M/15.3M [00:00<00:00, 28.1MB/s]Traceback (most recent call last):                                                                                                                                                                                                                                             
  File "run_mlm_tf.py", line 794, in <module>                                                                                                                                                                                                                                  
    main()                                                                                                                                                                                                                                                                     
  File "run_mlm_tf.py", line 425, in main                                                                                                                                                                                                                                      
    raw_datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name, cache_dir=model_args.cache_dir)                                                                                                                                                           File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/load.py", line 843, in load_dataset                                                                                                                                                                         
    builder_instance.download_and_prepare(                                                                                                                                                                                                                                     
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 608, in download_and_prepare                                                                                                                                                              
    self._download_and_prepare(                                                                                                                                                                                                                                                
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 698, in _download_and_prepare                                                                                                                                                                 verify_splits(self.info.splits, split_dict)                                                                                                                                                                                                                                  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/utils/info_utils.py", line 74, in verify_splits                                                                                                                                                             
    raise NonMatchingSplitsSizesError(str(bad_splits))                                                                                                                                                                                                                         
datasets.utils.info_utils.NonMatchingSplitsSizesError: [{'expected': SplitInfo(name='validation', num_bytes=38165657946, num_examples=13799838, dataset_name='c4'), 'recorded': SplitInfo(name='validation', num_bytes=37875873, num_examples=13863, dataset_name='c4')}] 

## Environment info
- `datasets` version: 1.10.2
- Platform: Linux-5.4.0-58-generic-x86_64-with-glibc2.29
- Python version: 3.8.10
- PyArrow version: 4.0.1 
 @bhavitvyamalik @lhoestq , just tried the above and got:
>>> a=datasets.load_dataset('c4','en.realnewslike')
Downloading: 3.29kB [00:00, 1.66MB/s]                                                                                                                                                                                                                                          
Downloading: 2.40MB [00:00, 12.6MB/s]                                                                                                                                                                                                                                          
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/load.py", line 819, in load_dataset
    builder_instance = load_dataset_builder(
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/load.py", line 701, in load_dataset_builder
    builder_instance: DatasetBuilder = builder_cls(
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 1049, in __init__
    super(GeneratorBasedBuilder, self).__init__(*args, **kwargs)
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 268, in __init__
    self.config, self.config_id = self._create_builder_config(
  File "/home/dshirron/.local/lib/python3.8/site-packages/datasets/builder.py", line 360, in _create_builder_config
    raise ValueError(
ValueError: BuilderConfig en.realnewslike not found. Available: ['en', 'realnewslike', 'en.noblocklist', 'en.noclean']
>>> 

datasets version is 1.11.0
