chore: cleanup documentation issues

[baronkobama]

Summary

This PR cleans up issues with the current master branch documentation. Most of these issues stemmed from #1476 (my bad lol), but a few are newly discovered/created issues.

A couple issues are yet to be solved and I'd like to get that done in this PR. These are:

• The ForumChannel reference's attribute and method table are currently duplicated (I have absolutely zero clue why, please help me).
• An ApplicationContext property that was intended to be fixed in Large code/documentation cleanup #1476 but remains with a broken reference.
• Guild.create_auto_moderation_rule contains 4 broken type references to objects that are not placed anywhere on the documentation.

I'm really not sure how to handle any of the above, any contributions are welcomed. PR will (probably) remain in draft status until the above reach some sort of solution.

Information

• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters).
• This PR is a breaking change (e.g. methods or parameters removed/renamed).
• This PR is not a code change (e.g. documentation, README, typehinting, examples, ...).

Checklist

• I have searched the open pull requests for duplicates.
• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
• If type: ignore comments were used, a comment is also left explaining why.

[JustaSqu1d]

The ForumChannel reference's attribute and method table are currently duplicated (I have absolutely zero clue why, please help me).

It could be that there are two ForumChannels which messed up Sphinx documentation.

[baronkobama]

It could be that there are two ForumChannels which messed up Sphinx documentation.

Good catch, not sure how that happened, but it definitely looks to be the source of the problem. Should be fixed in latest commit.

[baronkobama]

Marking this PR as ready for review. The two remaining issues listed in the summary may or may not be addressed with this PR since I don't want this PR going stale.