[Improvement][Seatunnel-web] Support H2 database in integration tests

[arshadmohammad]

Purpose of this pull request

Check list

• Code changed are covered with tests, or it does not need tests for reason:
• If any new Jar binary package adding in your PR, please add License Notice according
  New License Guide
• If necessary, please update the documentation to describe the new feature. https://github.com/apache/seatunnel/tree/dev/docs

[arshadmohammad]

integration test execution result using default h2 database

[arshadmohammad]

integration test execution result using mysql data by passing -DdbType=mysql

[arshadmohammad]

Thanks @Hisoka-X for reviewing and merging this PR.

[arshadmohammad]

With the removal of the dependency on an external database, integration tests can now run using an in-memory H2 database. However, the Seatunnel distribution is still required.
@Hisoka-X, could you provide guidance on how to run the integration tests as part of the PR CI process?

[Hisoka-X]

The test in CI in fact is trigger mvn script. Please refer https://github.com/apache/seatunnel/blob/dev/.github/workflows/backend.yml#L645

We already have some config in https://github.com/apache/seatunnel-web/blob/main/.github/workflows/backend.yml#L161
Just need add new script into backend.yml.

However, the Seatunnel distribution is still required.

We can execute mvn install before test with seatunnel-web.

1. Checkout seatunnel dev branch, https://github.com/apache/seatunnel/blob/dev/.github/workflows/backend.yml#L86
2. execute mvn install and other script which execute in local before. (Like set SEATUNNEL_HOME)
3. Run mvn test by mvn script.
   all these step can be done with github action run https://github.com/apache/seatunnel/blob/dev/.github/workflows/backend.yml#L315