[FLINK-34060][table] Migrate UserDefinedTableAggFunctions to JavaUserDefinedTableAggFunctions

[xuyangzhong]

What is the purpose of the change

The Top3 function emits a tuple of (entry.getKey, entry.getKey) see UserDefinedTableAggFunctions.scala#L127, which is peculiar.

Meanwhile, consider getting the scala-free goal; it's time to migrate this class to the JavaUserDefinedTableAggFunctions, and revisit the implementation.

Brief change log

• Fix peculiar logic about Top3, Top3WithMapViewAccum and Top3WithRetractInputAcc used for test
• Move all udx in UserDefinedTableAggFunctions to JavaUserDefinedTableAggFunctions

Verifying this change

Existent tests can cover these changes.

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?

[flinkbot]

CI report:

• ebc29752d43c83eef334c29498202c888142893f Azure: FAILURE

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