[3.15] cp315 smoke tests (`tests/smoke_test.py`, `tests/lib-injection`) green → flip cp315 wheel job from `allow-fail` to required

[vlad-scherbich]

note: blocked by #17810

Tracked under parent: #17809

Tier: A
Section: Needs an owner — new work

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Original row from the parent tracker:

• cp315 smoke tests (tests/smoke_test.py, tests/lib-injection) green → flip cp315 wheel job from allow-fail to required — @DataDog/python-guild @DataDog/apm-core-python

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