[FLINK-32712][format/json] enhance flink ogg-json format

[yuanoOo]

What is the purpose of the change

The BEFORE field in ogg-json can be configured to contain no table fields, as in the ogg-json example below.

{
  "table": "ZBZZZ",
  "op_type": "U",
  "op_ts": "2023-07-20 21:45:34.860817",
  "current_ts": "2023-07-21T05:45:36.615000",
  "pos": "00002564940142073691",
  "before": {},
  "after": {
      "ID": 1461242,
      "PROPERTY_01": "tc",
      "PROPERTY_02": null,
      "PROPERTY_03": null,
      "PROPERTY_04": "K",
      "PROPERTY_05": "5",
      "PROPERTY_06": null,
      "PROPERTY_07": null,
      "PROPERTY_08": null,
      "PROPERTY_09": null,
      "PROPERTY_10": null
  }
}

For this case, ogg-json format should not send a Record of type UPDATE_BEFORE downstream。 Worse, it can sometimes cause the flink job to crash out.
 

Brief change log

• add logic for handling "before":{} case.
• add the test data for this case.

Verifying this change

This change is already covered by existing tests, such as OggJsonSerDeSchemaTest.
so I added the test data for this case.

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

• Dependencies (does it add or upgrade a dependency): (yes / no) no
• The public API, i.e., is any changed class annotated with @Public(Evolving): (yes / no) no
• The serializers: (yes / no / don't know) no
• The runtime per-record code paths (performance sensitive): (yes / no / don't know) no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (yes / no / don't know) no
• The S3 file system connector: (yes / no / don't know) no

Documentation

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

[flinkbot]

CI report:

• 9c5472f Azure: SUCCESS

Bot commands

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[yuanoOo]

@flinkbot run azure

[lsyldliu]

@yuanoOo Thanks for contribution, This enhance looks make sense to me.