[helm] Isolate defaultUser handling in createUserJob

[nhuantho]

What:

• When I read #53198 and then checked the {release-name}-create-user-job, I saw that it is used only to create a user via the airflow users command (FAB CLI Commands). Therefore, I believe that defaultUser should not be part of the webserver or apiServer.
• From my perspective, we should decouple the responsibilities of each service. Currently, createUserJob depends on the webserver, but the webserver has been replaced by the apiServer. As a result, we should move defaultUser to the apiServer configuration.

Solution:

• Move defaultUser into createUserJob to isolate the functionality of createUserJob.
• Remove the usage of webserver.defaultUser from the Helm chart and related tests.

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[jscheffl]

Technically you are right and thanks for the contribution.

Nevertheless we have usually a semantic release mindset, so if somebody is using Helm chart 1.18.0 so far and upgrades, the user creation would be missing. In my view a backwards-compatibility is needed for people migrating so that older values are also supported. Or we need to postpone this change to a version 2.0 where we can introduce breaking changes.

@jedcunningham WDYT?

[nhuantho]

Thanks @jscheffl, I agree with you, so can you create milestones for version 2.0 (Will version 2.0 deprecate webserver) .
I think we can add some issues here (it is only my suggestion):

• Deprecate webserver in helm chart
• Add a tool to migrate webserver config to apiServer config 57519
• Update parameters
  • Add overwrite section page to give the main components in helm chart and explain overview about their goals.
  • Remove webserver parameters.
  • Split parameters for each job (currently, all parameters of all jobs are in a table).
• Update production-guide related to webserver

I am willing to contribute these issues.