[CI/Build] Skip Idefics3 and SmolVLM generation test again

[Isotr0py]

Purpose

• Idefics3 HF model is still broken even after Transformers v4.55.2 patch release with device mismatch fix.
• Let's skip it until next release with corresponding fix (Fix idefics3 vision embeddings indices dtype huggingface/transformers#40360)...
  (This really drives me crazy 🤪)

Test Plan

Test Result

(Optional) Documentation Update

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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.

[gemini-code-assist]

Code Review

This pull request aims to temporarily disable generation tests for Idefics3 and SmolVLM by bumping the minimum required transformers version, due to an issue in recent releases.

The change for Idefics3ForConditionalGeneration correctly sets min_transformers_version to 4.56, which will skip the tests on older versions. However, for SmolVLMForConditionalGeneration, max_transformers_version is used instead of min_transformers_version. This appears to be a mistake, as it will not prevent the tests from running on the problematic 4.55.x versions. I've added a comment with a suggested fix to align the behavior for both models.

[github-actions]

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