Cleanup imports and improve CS rules

[DerManoMann]

No description provided.

[github-actions]

Created backport PR for 5.x:

• [Backport #1964 to 5.x] Cleanup imports and improve CS rules #1965 with remaining conflicts!

Please cherry-pick the changes locally and resolve any conflicts.

git fetch origin backport-1964-to-5.x
git worktree add --checkout .worktree/backport-1964-to-5.x backport-1964-to-5.x
cd .worktree/backport-1964-to-5.x
git reset --hard HEAD^
git cherry-pick -x 380227f15abb0af2c961b11e4406d231a9a5bf65
git push --force-with-lease