Fix RESOURCE_EXHAUSTED admin quota limit exceed failures in test pipelines.

[rahul2393]

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Is your feature request related to a problem? Please describe.
Test pipelines in repo sometimes fail with RESOURCE_EXHAUSTED errors.

Describe the solution you'd like
Tests should automatically retry RESOURCE_EXHAUSTED errors.

Describe alternatives you've considered
Having separate project per test pipeline can also be done but managing multiple auth and project can be overwork.

Additional context
https://btx.cloud.google.com/invocations/69b0a8f0-76b7-4462-a116-af8bb260dc36/targets/cloud-devrel%2Fclient-libraries%2Fjava%2Fjava-spanner%2Fpresubmit%2Fintegration-directpath-enabled;config=default/log