[Docs] Update documentation and review docstrings

[sdiazlor]

Description

• Deleted parameter explanations from a how-to guide for maintenance and updated the code snippets. Added note referring to API reference.
• Reviewed default mkdocstrings options in mkdocs.yml for maintenance as most files used the same options. Removed extra options from API reference. Docstrings style chosen as google, because most of them was using it.
• Reviewed docstrings: coherence across classes and methods, typos, duplicated or missing information. Used ```python instead of >>>, so the example code snippets can be directly run when copied.
• In questions, I also reviewed the type hinting for labels and the error message.

Closes #5373

Type of change

• Documentation update

How Has This Been Tested

Checklist

[github-actions]

Docs for this PR have been deployed hidden from versioning: https://docs.argilla.io/docs_5373-update-documentation-and-review-docstrings

[sdiazlor]

I still didn't apply the below changes, but discovered these options of the mkdocstrings module with the tags. I believe they can help the developers when searching in the API reference. WDYT? cc @davidberenstein1957 @burtenshaw

[davidberenstein1957]

@sdiazlor please add the tags, they are really helpful