Librarian Bot: Add base_model information to model

This pull request aims to enrich the metadata of your model by adding [`google/mt5-small`](https://huggingface.co/google/mt5-small) as a `base_model` field, situated in the `YAML` block of your model's `README.md`.

How did we find this information? We performed a regular expression match on your `README.md` file to determine the connection.

**Why add this?** Enhancing your model's metadata in this way:
- **Boosts Discoverability** - It becomes straightforward to trace the relationships between various models on the Hugging Face Hub.
- **Highlights Impact** - It showcases the contributions and influences different models have within the community.

For a hands-on example of how such metadata can play a pivotal role in mapping model connections, take a look at [librarian-bots/base_model_explorer](https://huggingface.co/spaces/librarian-bots/base_model_explorer).

This PR was requested via the [Librarian Bot](https://huggingface.co/librarian-bot) [metadata request service](https://huggingface.co/spaces/librarian-bots/metadata_request_service) by request of [davanstrien](https://huggingface.co/davanstrien)

README.md

@@ -1,4 +1,6 @@
 ---
+language:
+- en
 license: apache-2.0
 tags:
 - summarization
@@ -7,12 +9,13 @@ datasets:
 - multi_news
 metrics:
 - rouge
+base_model: google/mt5-small
 model-index:
 - name: mt5-small-multi-news
   results:
   - task:
-      name: Sequence-to-sequence Language Modeling
       type: text2text-generation
+      name: Sequence-to-sequence Language Modeling
     dataset:
       name: multi_news
       type: multi_news
@@ -20,20 +23,18 @@ model-index:
       split: validation
       args: default
     metrics:
-    - name: Rouge1
-      type: rouge
+    - type: rouge
       value: 22.03
-    - name: Rouge2
-      type: rouge
+      name: Rouge1
+    - type: rouge
       value: 6.95
-    - name: Rougel
-      type: rouge
+      name: Rouge2
+    - type: rouge
       value: 18.41
-    - name: Rougelsum
-      type: rouge
+      name: Rougel
+    - type: rouge
       value: 18.72
-language:
-- en
+      name: Rougelsum
 ---
 
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