Add check for is comparison with mutable initialisers to rule F632

[jesse1412]

Summary

Adds an extra check to F632 to check for any is comparisons to a mutable initialisers.
Implements #8589 .

Example:

named_var = {}
if named_var is {}:  # F632 (fix)
    pass

The if condition will always evaluate to False because it checks on identity and it's impossible to take the same identity as a hard coded list/set/dict initializer.

Multiple test cases were added to ensure the rule works + doesn't flag false positives + the fix works correctly.

[github-actions]

ruff-ecosystem results

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Linter (preview)

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Formatter (preview)

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[vinhocent]

Just wondering - what was the original reasoning for not using a match statement in is_constant() @charliermarsh ?

[zanieb]

We should probably gate this change to only apply when preview mode is enabled per the versioning policy as I think it fits into

The scope of a stable rule is significantly increased

Note on how to do this in another pull request #8608 (comment)

[zanieb]

Thanks for contributing :) the rest of the implementation looks good to me. I don't have the answer to your question though.

[jesse1412]

I thiiink I've added the preview flag. And thanks for the encouraging words!

[charliermarsh]

Great, thank you!