ruff

a93992fa - [`flake8-return`] Stabilize only add `return None` at the end when fixing `implicit-return` (`RET503`) (#18516)

[`flake8-return`] Stabilize only add `return None` at the end when fixing `implicit-return` (`RET503`) (#18516) This involved slightly more code changes than usual for a stabilization - so maybe worth double-checking the logic! I did verify by hand that the new stable behavior on the test fixture matches the old preview behavior, even after the internal refactor.