Remove remaining tests from collection

[mollyxu]

Remove remaining skipped tests from collection in internal environment

Prevent internal CI failures from skipped tests by excluding skipped tests from collection in internal environment.

TorchCodec tests were flaky / broken internal because:

• Tests were using runtime pytest.skip() calls, so they were collected but then skipped during execution

Follow up to #1068

Changes Made

1. Replaced all instances of pytest.skip() with @pytest.mark.skipif()

2. Updated conftest.py to document our test collection logic

3. Updated all_supported_devices in conftest.py to accept optional list of marks to add to cuda devices

4. Removed skip that was no longer applicable in test_10bit_videos

[meta-codesync]

@mollyxu has imported this pull request. If you are a Meta employee, you can view this in D89555188.

[mollyxu]

no longer applicable because the BETA interface fallsback to the CPU now

[mollyxu]

to skip tests that depend on both format and encoding parameters
(ie. avi / flv with yuv444p)

[Dan-Flores]

Ideally, we would handle all parametrization for a test in one place.

By adding a helper function, it is harder to add new test cases and to understand what is being tested. If we cannot fit the logic into a pytest.param, it might be best to let these test cases appear skipped on CI.

This is one of the downsides to having a test with many parameters - we cannot easily isolate these parameter combinations that fail.

[Dan-Flores]

Nice job on these! It is easier to understand where the test is skipped now that the skip occurs in the parametrization.

[Dan-Flores]

Thanks for working on this @mollyxu! Lets focus these changes on the cases where we can simply swap out pytest.skip. I left some comments on the changes where I think the value tradeoff for increased complexity is less clear.

[Dan-Flores]

I see how this covers the test skip in test_get_frame_at_av1, its a tricky case.

Since there's only one case where we need the cuda_marks argument, I'm not sure its worth exposing at the moment. While other usages of all_supported_devices are not affected by the new arg, its not obvious that this function should be used to add marks to the cuda device params.

In this case, it might be bes to keep the pytest.skip in the test_get_frame_at_av1