Flink: Improvements for iceberg sink connector.

[openinx]

In this patch, we have several minor issues to follow up for flink sink connector:

• Support multiple iceberg sinks in the same flink job. discussion.
• provide a method to set user-provided write parallelism in FlinkSink#Builder.
• The netflix team have improved their flink sink by buffering all the uncommitted data files in a separate manifest file to reduce the state size. It would be really helpful if users put their data files and metstore in two different cloud region, because we could keep the job going even if we fail to commit to iceberg sometimes. discussion

[stevenzwu]

just want to add another unaddressed comment regarding distinguishing DataFile from different Flink checkpoints.

[github-actions]

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[github-actions]

This issue has been closed because it has not received any activity in the last 14 days since being marked as 'stale'