Disable failing GPT-OSS Eval (Blackwell) for now

[mgoin]

Purpose

Test Plan

Test Result

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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.
• (Optional) Release notes update. If your change is user facing, please update the release notes draft in the Google Doc.

[gemini-code-assist]

Code Review

This pull request disables a failing GPT-OSS evaluation test for Blackwell GPUs in the CI pipeline by marking it as optional. While this is a reasonable temporary measure to unblock development, it introduces a risk of the test remaining disabled indefinitely. My review includes a suggestion to add a tracking issue to ensure the test is eventually fixed and re-enabled.

[gemini-code-assist]

While disabling a failing test is a reasonable temporary measure to unblock the CI, there's a risk it might be forgotten and left disabled permanently. This would prevent catching regressions in the GPT-OSS evaluation on Blackwell GPUs. To mitigate this, it's highly recommended to create a tracking issue to fix and re-enable this test, and reference the issue number in a comment here.

  optional: true # TODO(<issue-link>): Re-enable this test after fixing the failures.