[Feature][Sort] Add batch end-to-end test for Kafka v1.18 connector

[PeterZh6]

Description

Parent Issue #11419
Related Issue #11494

Flink uses stream mode as default mode of execution. Current end-to-end test introduced by #11494 adopts stream mode. Additional batch-executed end-to-end test need to be enforced to better verify the requirements for #11419, and potentially for all the sub-issues under #11417.

Use case

No response

Are you willing to submit PR?

• Yes, I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[PeterZh6]

While working on this, I started to wonder about the best approach for conducting such a test:

Should I simply use Flink's batch execution mode with the command-line arguments (i.e., --execution.mode batch) when submitting the Flink job, and test it that way?

Or do I need to tailor the test for each connector (in this case, Kafka) since different connectors can behave differently in batch mode?

I’m uncertain whether a one-size-fits-all approach will work, or if I need to adjust configurations or setup steps specific to Kafka or the InLong Sort connector.

Has anyone faced this scenario or can provide insights on how best to test batch support with Flink connectors?