[BP-2.0][FLINK-37458][datastream] Forbid enableAsyncState() for synchronous operators

[fredia]

Backport #26283 to release-2.0

What is the purpose of the change

Throw an exception when enableAsyncState() for synchronous operators.

Brief change log

• Override OneInputTransformation#enableAsyncState()

Verifying this change

• JobGraphGeneratorTestBase#testEnableAsyncStateForSyncOperatorThrowException

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (no)
• The serializers: (no)
• The runtime per-record code paths (performance sensitive): (no)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (no)
• The S3 file system connector: (no)

Documentation

• Does this pull request introduce a new feature? (no)
• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

[Zakelly]

Thanks for the backport, LGTM

[flinkbot]

CI report:

• dc23f22 Azure: SUCCESS

Bot commands

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• @flinkbot run azure re-run the last Azure build

[davidradl]

I am curious shouldn't this be an error?
As is the caller amkes this call anf would assume that async is enabled, but it is not.

[fredia]

@flinkbot run azure