[damccorm]

Summary

Fixes flaky DeadlineExceededException failures in PostCommit SQL (PubsubTableProviderIT and BeamSqlLineIT, e.g. https://github.com/apache/beam/actions/runs/42312418759, https://github.com/apache/beam/actions/runs/41878199992, https://github.com/apache/beam/actions/runs/41779718356).

In com.google.cloud.pubsub.v1, TopicAdminClient.createTopic and SubscriptionAdminClient.createSubscription have a 60s RPC timeout with no default retries configured on DEADLINE_EXCEEDED / UNAVAILABLE. When a single createSubscription or createTopic RPC in TestPubsub.initializePubsub or TestPubsubSignal.initializePubsub stalls for 60s against pubsub.googleapis.com, the test immediately fails with com.google.api.gax.rpc.DeadlineExceededException.

This PR adds a 3-attempt retry helper in TestPubsub (used by both TestPubsub and TestPubsubSignal, similar to PubsubResourceManager) that retries createTopic and createSubscription on DeadlineExceededException and UnavailableException (treating AlreadyExistsException on retry as success).

Verification

• Triggered PostCommit SQL on this branch: https://github.com/apache/beam/actions/runs/42317114490

[damccorm]

/gemini review

[damccorm]

/gemini review

[github-actions]

📋 Review Summary

This PR introduces 3-attempt retry logic for Pub/Sub topic and subscription creation in TestPubsub, TestPubsubSignal, and PubsubWriteIT to mitigate flaky integration test failures caused by transient DEADLINE_EXCEEDED and UNAVAILABLE errors. The implementation cleanly handles AlreadyExistsException / ALREADY_EXISTS on retries and preserves teardown state invariants.

🔍 General Feedback

• The retry wrappers are well-scoped, idiomatic, and align with existing resource management patterns in the codebase.
• Treating AlreadyExistsException (and Status.Code.ALREADY_EXISTS) as success on retry safely handles cases where a previous attempt succeeded server-side before timing out.

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