ruff

e39298dc - Use UTF-8 as default encoding in `unspecified-encoding` fix (#12370)

Use UTF-8 as default encoding in `unspecified-encoding` fix (#12370) ## Summary This is the _intended_ default that PEP 597 _wants_, but it's not backwards compatible. The fix is already unsafe, so it's better for us to recommend the desired and expected behavior. Closes https://github.com/astral-sh/ruff/issues/12069.