[Hotfix][Zeta] Fix submit job throw jobId NPE

[chaorongzhi]

Purpose of this pull request

Fix the problem that jobId is null and job submission fails, and add documentation comments.

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
• If you are contributing the connector code, please check that the following files are updated:
  1. Update change log that in connector document. For more details you can refer to connector-v2
  2. Update plugin-mapping.properties and add new connector information in it
  3. Update the pom file of seatunnel-dist
• Update the release-note.

[liugddx]

Can you add a unit test?

[chaorongzhi]

Can you add a unit test?

Sure, I'll add unit tests to the e2e module.

[chaorongzhi]

Can you add a unit test?

@liugddx PTAL, I have added unit test.

[Hisoka-X]

cc @zhibinF maybe you should take a look.