Add tests for common compat standard utilities

[dhkim1920]

Add coverage for the compatibility imports exposed by common.compat.standard.utils.

The tests verify every name in __all__ resolves through the compatibility import map and that unknown attributes retain the expected AttributeError contract. This removes the corresponding entry from OVERLOOKED_TESTS.

related: #35442

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Was generative AI tooling used to co-author this PR?

• Yes — Codex (GPT-5)

Generated-by: Codex (GPT-5) following the guidelines

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Drafted-by: Codex (GPT-5); reviewed by @dhkim1920 before posting

[fat-catTW]

Thanks for the contribution!

I think this test should use an independent expected list instead of parametrizing from utils.__all__.

Right now utils.__all__ is derived from _IMPORT_MAP, so the test only checks the exports that the implementation currently advertises. If an expected compat export like prepare_virtualenv, SkipMixin, or one of the XCom constants were accidentally removed from _IMPORT_MAP, it would also disappear from __all__, and this test would still pass without noticing.

Could we make the expected public exports explicit in the test, then assert both set(utils.__all__) and that each expected name resolves successfully? That would make the test protect the actual compatibility contract before removing this file from OVERLOOKED_TESTS.

[dhkim1920]

@fat-catTW
Thanks for the thoughtful review. You're right that deriving the test cases from __all__ could miss accidental removals. I've updated the test to define the expected exports explicitly, assert that __all__ matches them, and verify that each export resolves successfully.