Helm chart fixes in pod template

[fllaca]

I came with some little issues while testing the chart in this repo locally, here I'm bundling some fixes to them:

• default pod_template image to defaultAirflowRepository:defaultAirflowTag
• fix never-ending git-sync init containers
• fix broken reference to volume

[boring-cyborg]

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[github-actions]

The Workflow run is cancelling this PR. It has some failed jobs matching ^Pylint$,^Static checks$,^Build docs$,^Spell check docs$,^Backport packages$,^Checks: Helm tests$,^Test OpenAPI*.

[github-actions]

The Workflow run is cancelling this PR. It has some failed jobs matching ^Pylint$,^Static checks$,^Build docs$,^Spell check docs$,^Backport packages$,^Checks: Helm tests$,^Test OpenAPI*.

[potiuk]

Hello @fllaca, Can you please rebase this one to latest master. We fixed (hopefully) a problem with queues of jobs for GitHub actions and I think when you rebase, it shoudl run much faster (more info on devlist shortly).

[github-actions]

The Workflow run is cancelling this PR. It has some failed jobs matching ^Pylint$,^Static checks$,^Build docs$,^Spell check docs$,^Backport packages$,^Checks: Helm tests$,^Test OpenAPI*.

[fllaca]

I couldn't find a way to assert that this value should be the default defaultAirflowRepository without hardcoding the test with apache/airflow:1.10.12 (copying from values.yaml). If that hardcoded value in the assertion is fine, I can change the test back to equal assert.

[fllaca]

Hi @potiuk! thanks for taking a look to this. I just rebased and added some helm test. One of the kubernetes test is failing (CI Build / K8s: 3.7 v1.17.5 image (pull_request)), would you mind checking it? I went to the build logs but I'm not very sure what is wrong there and/or if it is related to the changes in this PR.

[mik-laj]

A very interesting change. I did not know the GIT_ONE_TIME option. Thanks for adding that. In our case, it very makes sense.

I also see that you made sure that this change had good unit test coverage. We are working to modernize our unit tests to overcome some of the limitations of Helm-unittest. One of its limitations even you have encountered - #11511 (comment)
I would be happy if you could share your experience on this ticket: #11657
Can you also help us?

[boring-cyborg]

Awesome work, congrats on your first merged pull request!