Fix F701 to F707 errors in tests (#19125)
## Summary
Per @ntBre in https://github.com/astral-sh/ruff/pull/19111, it would be
a good idea to make the tests no longer have these syntax errors, so
this PR updates the tests and snapshots.
`B031` gave me a lot of trouble since the ending test of declaring a
function named `groupby` makes it so that inside other functions, it's
unclear which `groupby` is referred to since it depends on when the
function is called. To fix it I made each function have it's own `from
itertools import groupby` so there's no more ambiguity.
