[FLINK-19868][csv] Csv Serialization schema contains line delimiter

[SteNicholas]

What is the purpose of the change

CsvRowSerializationSchema and CsvRowDataSerializationSchema serialize Row and RowData to byte array end with \n at default. For the row-wise formats, it should consume and produce the bytes for a row. csv.line-delimiter option is not a good option for csv format and shoud be removed for CsvRowSerializationSchema and CsvRowDataSerializationSchema to not append a new line.

Brief change log

• CsvSchema in CsvRowSerializationSchema and CsvRowDataSerializationSchema configures the line separator to empty string.
• line-delimiter option in CsvFormatFactory, CsvRowFormatFactory and CsvFileSystemFormatFactory is removed.
• *CsvFileSystemFormatFactory encodes RowData record end with line delimiter \n to write.

Verifying this change

• Remove the line delimiter config of test cases in CsvRowDataSerDeSchemaTest and CsvRowDeSerializationSchemaTest to verify whether the byte array which CsvRowSerializationSchema and CsvRowDataSerializationSchema serialize Row and RowData to includes line delimiter \n.
• Remove theline-delimiter option of test cases in CsvFormatFactoryTest and CsvRowFormatFactoryTest to verify whether the line-delimiter option could be removed normally.

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

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

Documentation

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

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CI report:

• a00a1de Azure: FAILURE

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[SteNicholas]

@wuchong @JingsongLi , could you please help to review this pull request if you are available?

[wuchong]

LGMT.

Waiting for the build to pass.

[wuchong]

The failed e2e test seems not related to this PR.

Will merge it.