fix: avoid casting tuples after Dataset.map
{'login': 'szmoro', 'id': 5697926, 'node_id': 'MDQ6VXNlcjU2OTc5MjY=', 'avatar_url': 'https://avatars.githubusercontent.com/u/5697926?v=4', 'gravatar_id': '', 'url': 'https://api.github.com/users/szmoro', 'html_url': 'https://github.com/szmoro', 'followers_url': 'https://api.github.com/users/szmoro/followers', 'following_url': 'https://api.github.com/users/szmoro/following{/other_user}', 'gists_url': 'https://api.github.com/users/szmoro/gists{/gist_id}', 'starred_url': 'https://api.github.com/users/szmoro/starred{/owner}{/repo}', 'subscriptions_url': 'https://api.github.com/users/szmoro/subscriptions', 'organizations_url': 'https://api.github.com/users/szmoro/orgs', 'repos_url': 'https://api.github.com/users/szmoro/repos', 'events_url': 'https://api.github.com/users/szmoro/events{/privacy}', 'received_events_url': 'https://api.github.com/users/szmoro/received_events', 'type': 'User', 'site_admin': False}
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_The documentation is not available anymore as the PR was closed or merged._
This PR updates features.py to avoid casting tuples to lists when reading the results of Dataset.map as suggested by @lhoestq [here](https://github.com/huggingface/datasets/issues/4676#issuecomment-1187371367) in https://github.com/huggingface/datasets/issues/4676.

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