[CI/Build] Skip Mllama HF runner tests with Transformers v4.55.0

[Isotr0py]

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

Purpose

• Fix [CI Failure]: Distributed Tests (2 GPUs) - Mllama TP=2 results divergence and deadlock issue #22559
• Transformers v4.55.0 has a regression issue about mllama, this PR skip them temporarily to make CI green until corresponding fix PR (Fix regression in mllama vision encoder huggingface/transformers#40083) is included in patch release.

Test Plan

pytest -s -v tests/models/multimodal/generation/test_mllama.py -k test_models_distributed

Test Result

Test should be skipped on CI now.

(Optional) Documentation Update

[github-actions]

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[gemini-code-assist]

Code Review

This pull request introduces a temporary fix to skip Mllama tests on Transformers v4.55.0 due to a regression, which is a good approach to keep the CI green. My main feedback is to refactor the duplicated pytest.mark.skipif condition into a shared constant to improve code maintainability. This will make it easier to remove the skip condition once the upstream issue is resolved.

[gemini-code-assist]

To improve maintainability and reduce code duplication, it's better to define this skipif condition as a constant and reuse it for all affected tests. This will make it easier to remove the skip condition in the future when the upstream issue is resolved.

Please define the following constant at the top of the file, for example after the imports:

MMLAMA_REGRESSION_TRANSFORMERS_4_55_0 = pytest.mark.skipif(
    TRANSFORMERS_VERSION == "4.55.0",
    reason="Transformers v4.55.0 has a regression issue on mllama, "
    "see: https://github.com/huggingface/transformers/pull/40083")

Then, you can apply it to this test and the others (test_models_multi_leading_images, test_models_interleaved_images, test_models_distributed) like this:

@MMLAMA_REGRESSION_TRANSFORMERS_4_55_0

[DarkLight1337]

Thanks for identifying the root cause!