[FLINK-22297][python] Perform early validation for the result of Pand…

[dianfu]

What is the purpose of the change

This pull request performs early validation for the result of Pandas UDF, e.g. ensure the result length is equal to the input length, validates the result type, etc

Verifying this change

This change added tests test_invalid_pandas_udf in test_pandas_udfs.py.

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/Mesos, 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)

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Automated Checks

Last check on commit 4efbadb (Sat Aug 28 11:15:19 UTC 2021)

Warnings:

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Review Progress

• ❓ 1. The [description] looks good.
• ❓ 2. There is [consensus] that the contribution should go into to Flink.
• ❓ 3. Needs [attention] from.
• ❓ 4. The change fits into the overall [architecture].
• ❓ 5. Overall code [quality] is good.

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CI report:

• 4efbadb Azure: PENDING

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[HuangXingBo]

LGTM

[dianfu]

Closed via 599b7ee