[FLINK-33116][tests][release-1.15] Fix CliClientTest.testCancelExecutionInteractiveMode fails with NPE

[Jiabao-Sun]

What is the purpose of the change

[FLINK-33116][tests] Fix CliClientTest.testCancelExecutionInteractiveMode fails with NPE

Sep 18 02:26:15 02:26:15.743 [ERROR] org.apache.flink.table.client.cli.CliClientTest.testCancelExecutionInteractiveMode  Time elapsed: 0.1 s  <<< ERROR!
Sep 18 02:26:15 java.lang.NullPointerException
Sep 18 02:26:15 	at org.apache.flink.table.client.cli.CliClient.closeTerminal(CliClient.java:284)
Sep 18 02:26:15 	at org.apache.flink.table.client.cli.CliClient.close(CliClient.java:108)
Sep 18 02:26:15 	at org.apache.flink.table.client.cli.CliClientTest.testCancelExecutionInteractiveMode(CliClientTest.java:314)
Sep 18 02:26:15 	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 

Brief change log

The CliClient is not thread-safe: The close call fails with a NullPointerException because CliClient.close() calls closeTerminal() if a terminal set. But the test finishes the client.executeInInteractiveMode() in a separate thread which calls closeTerminal() in the end as well.

Using CheckedThread instead of Thread.

Verifying this change

This change is already covered by existing tests.

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)

[flinkbot]

CI report:

• adce914 Azure: SUCCESS

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[Jiabao-Sun]

@flinkbot run azure

[XComp]

1.15 is not supported anymore. I'm gonna close this one without merging.

[Jiabao-Sun]

1.15 is not supported anymore. I'm gonna close this one without merging.

OK. Thanks.