[FLINK-36154][formats] Support deserialize json ignore key case

[KevinyhZou]

What is the purpose of the change

Support to parse json string ignore the key case while match to schema field name. Sometimes we defined a table in flink sql, like test_tbl(a String, b String), but sometimes when the json string from the mq(kafka/pulsar) may be like {"A":"a", "B":"b"}, and the field a and b will not be parsed as the case of key not match.

Brief change log

Introduce a config json.ignore-key-case to ignore the key case while parse json string.

Verifying this change

This change added tests and can be verified as follows:

add unit test testIgnoreKeyCase in JsonParserRowDataDeSerSchemaTest.java

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: (yes)
• 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)

[flinkbot]

CI report:

• de35f05 Azure: SUCCESS

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