Revert "[TPU][Bugfix] fix OOM issue in CI test"

[yaochengji]

The TPU CI test didn't pass with the fix.
Reverts #21550

[github-actions]

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[gemini-code-assist]

Code Review

This pull request reverts a previous change that modified the gpu_memory_utilization parameter for a TPU test. According to the description, the original change did not resolve the CI issue as intended. Reverting this change to restore the previous value is a logical step to stabilize the test suite. The change is simple, well-contained, and appropriate given the context.