Fix Dataproc triggers swallowing task cancellation

[atharvaajmera]

Summary

The triggerer tells migration, user action and shutdown apart only by asyncio.CancelledError propagating out of trigger.run(). The except asyncio.CancelledError handlers in DataprocSubmitTrigger.run(), DataprocSubmitJobDirectTrigger.run() and DataprocClusterTrigger.run() performed cleanup (cancel the job/cluster when safe_to_cancel()) but never re-raised, so a transient triggerer stall followed by trigger migration produced Trigger exited without sending an event. Dependent tasks will be failed. for every hosted deferred task instead of a transparent failover.

This is the same bug shape fixed for BigQueryInsertJobTrigger in #63730: add the missing bare raise after cleanup so cleanup_finished_triggers() takes the expected cancelled path. DataprocBatchTrigger, DataprocDeleteClusterTrigger and DataprocOperationTrigger are unaffected (no CancelledError handler, and except Exception does not catch CancelledError).

The cancellation tests now require CancelledError instead of also accepting StopAsyncIteration, and the cluster not-safe test actually injects cancellation (it previously completed before cancelling).

closes: #74087

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Was generative AI tooling used to co-author this PR?

• Yes — Muse Spark

Generated-by: Muse Spark following the guidelines

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[potiuk]

Approving. Re-raising CancelledError after cleanup lets the triggerer tell a reassigned trigger from a user cancel, while still emitting the final DELETING event first on older Airflow. The tightened tests now really cancel mid-await. Thanks!

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Drafted-by: Claude Code (Opus 5.5); reviewed by @potiuk before posting

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