feat: 🎸 add a function to get a dataset config's split names

[severo]

Also: pass additional arguments (use_auth_token) to get private configs + info of private datasets on the hub

Questions:

• I'm not sure how the versions work: I changed 1.12.1.dev0 to 1.12.1.dev1, was it correct?
  -> no: reverted
• Should I add a section in https://github.com/huggingface/datasets/blob/master/docs/source/load_hub.rst? (there is no section for get_dataset_infos)
  -> yes: added

[lhoestq]

Looks good to me ! Can you just merge master into your branch ?
We just deprecated the script_version parameter in favor of revision in load_dataset_builder and prepare_module, so you might need to do a few adjustments

[lhoestq]

Should I add a section in https://github.com/huggingface/datasets/blob/master/docs/source/load_hub.rst? (there is no section for get_dataset_infos)

Yes totally :) This tutorial should indeed mention this, given how fundamental it is

[lhoestq]

Thanks for the change and for adding it to the documentation :)
LGTM