Fix Helm GitSync dag volume mount

[matttattoli]

This fixes an issue where the workers cannot find the dag that is meant to run.

With git-sync enabled, the airflow_dag location is being set to where the dags are being cloned to, ex $AIRFLOWHOME/dags/repo/dags, but the subpath is remapping it to $AIRFLOWHOME/dags, thus the workers are not able to find the actually dag.

Also related: https://github.com/apache/airflow/blob/master/chart/templates/_helpers.yaml#L333

Removing the subpath resolves this issue. I locally ran the helm unit tests, and it succeeded.

[boring-cyborg]

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[KevinDukelow5]

👍

[boring-cyborg]

Awesome work, congrats on your first merged pull request!

[matttattoli]

@kaxil

I did some testing in master, and this is actually an invalid fix. It seems this is broken in branch v2-0-stable, but may have been fixed in master from some other commit. Please advise if you want to revert this PR.

[kaxil]

@matttattoli Sure if it is an invalid fix let's revert this and add a test so next time this test fails on such a change :)

We are planning to release Helm chart -- early May so only use it from Master instead of v2-0-stable

[matttattoli]

Revert PR here: #15390

Good to know, excited to hear the helm chart will be hosted soon. Will use master until then. Sorry for any inconvenience.