feat: adding pollingtimestamp metadata in bulk mode

[sachin-kansal]

Problem

While using bulk mode in JDBC source connector, polling time is not sent to the records metadata.
Hence insert field smt does not work to add polling time in the records.

Also whenever the jdbc is restarted polling is started again results in reading the table again or duplicate data and make difficult to bifurcate data which is added in the queue at each poll.

Solution

adding timestamp helps in the bifurcation.

Does this solution apply anywhere else?

• yes
• no

If yes, where?

Test Strategy

end to end dataflow check

Testing done:

• Unit tests
• Integration tests
• System tests
• Manual tests

Release Plan

[confluent-cla-assistant]

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✅ sachin-kansal
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[sachin-kansal]

@confluent-antonio please review my Pull Request

[sachin-kansal]

@aniketshrimal , could please review my Pull Request

[confluent-antonio]

@confluent-antonio please review my Pull Request

I'm sorry, I'm not a developer. I can't review your PR.