Fix type param formatting in funcdef with trailing comma

[sumezulike]

Description

This change adds additional checks to the decision whether to split a funcdef from the left or right-hand side. Specifically, this adds the following condition to should_split_funcdef_with_rhs: If a funcdef has type parameters and its parameters also have a trailing comma, return True, to indicate that the funcdef should not be split from the left first.

This fixes the bug described in #4254.

I am currently trying to also fix #3929 and #4071 since they seem related, but that seems to require a little more work. Any suggestions are appreciated.

Checklist - did you ...

• [x] Add an entry in CHANGES.md if necessary?
• [x] Add / update tests if necessary?
• [-] Add new / update outdated documentation?

[github-actions[bot]]

diff-shades reports zero changes comparing this PR (eb47bf05208ee616e86a515a466d964f68ebc45c) to main (f03ee113c9f3dfeb477f2d4247bfb7de2e5f465c).

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What is this? | Workflow run | diff-shades documentation

[sumezulike]

I thought it might be best to just submit a fix for the bug and work on the other changes in a separate PR. Happy about any feedback!

[sumezulike]

Closing this in favor of #4272