[FLINK-31673][jdbc-driver] Add e2e test for flink jdbc driver

[FangYongs]

What is the purpose of the change

Add e2e test for flink jdbc driver

Brief change log

• Add FlinkDriverE2eTest

Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

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

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

Documentation

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

[flinkbot]

CI report:

• 8ebc924 Azure: SUCCESS

Bot commands

The @flinkbot bot supports the following commands:

• @flinkbot run azure re-run the last Azure build

[FangYongs]

@flinkbot run azure

[FangYongs]

Hi @libenchao Please have a look at this PR when you are free, thanks

[libenchao]

@FangYongs By saying "e2e test", I mean the tests in flink-end-to-end-tests module. What do you think about adding it there?

[FangYongs]

Thanks @libenchao Sounds good to me, I'll move it there

[FangYongs]

Hi @libenchao I have update this PR for e2e test, please help to review when you are free, thanks

[libenchao]

@FangYongs Thanks for your updating, but in 'flink-end-to-end-tests', we usually run these tests via scripts, such as flink-end-to-end-tests/test-scripts/test_batch_sql.sh, in that way, we'll gain the benefits such as:

• The test will be run as a normal program instead of running in Junit environment, with real flink cluster (local cluster instead of mini cluster)
• These tests will be run in the special stage, not in the maven test stage, which is more flexible

[FangYongs]

Hi @libenchao I have rebased master and updated this PR, please have a look again when you are free, thanks

[libenchao]

Looks good to me, I only have one minor comment.

[libenchao]

Is this change expected?

[FangYongs]

@libenchao Yes, it will cause e2e test failed because the e2e test framework will check the .out log file and confirm that it is empty. I have confirmed this with @fsk119 that the System.out.println here is meaningless, we can remove them directly here.

[libenchao]

sounds good to me.