[CI][ROCm] Fix NIXL tests on ROCm

[NickLucche]

Follow up to #31491 for AMD mirror pipeline + timeout update from latest nightly run.

[gemini-code-assist]

Code Review

This pull request updates the CI configuration for NIXL tests, primarily for ROCm. The changes involve renaming a test script to a more generic version and adjusting test timeouts. The script consolidation simplifies the test execution logic, and the timeout adjustments are based on recent test runs, which should improve CI stability. The changes are straightforward and appear correct.

[tjtanaa]

The amdproduction marker does not trigger the unit test that is related to this PR. I have retriggered the AMDCI to include the test group that is going to be fixed by this PR. But not all test groups are passing. So, this is to use as reference to check if this PR fixes that specific test group only.

[DarkLight1337]

The test failed with RuntimeError: NIXL is not available

[tjtanaa]

@DarkLight1337 The most likely rocm/vllm-dev:base has not been propagated with the change from this PR 0f35429 . Will need @gshtras to trigger internal pipeline to update rocm/vllm-dev:base. So for now. As long as Nick has validated, I think it should be fine.

@NickLucche have you run the tests group locally on ROCm?

[NickLucche]

@tjtanaa @DarkLight1337 Test is running just fine locally with rixl build. It's failing after some time, but that's unrelated to the filename I am fixing here.