[FLINK-36816] Support source parallelism setting for JDBC connector

[grzegorz8]

Purpose of the change

Add new option scan.parallelism support for JDBC connector.

Part of FLINK-33261 FLIP-367: Support Setting Parallelism for Table/SQL Sources

The change is not backward compatible for versions <= 1.18. InputFormatProvider of(InputFormat<RowData, ?> inputFormat, @Nullable Integer sourceParallelism) was added in Flink 1.19. Therefore, we need to wait with this change until JDBC connector is no longer supporting Flink 1.18.

[davidradl]

could you add a link to some documentation for this - as there is for autocommit please.

[github-actions]

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[RocMarshal]

Thanks @grzegorz8 for the contribution .
Could you still work for this patch ?

If there is no response for an extended period, we will try to find other developers to continue advancing this patch. BTW, your initial contribution will be retained as a co-author in the commit message.

Looking forward to your back or reply!

[grzegorz8]

Thanks @grzegorz8 for the contribution . Could you still work for this patch ?

If there is no response for an extended period, we will try to find other developers to continue advancing this patch. BTW, your initial contribution will be retained as a co-author in the commit message.

Looking forward to your back or reply!

H! I'll try to rebase my PR with main soon.