Remove duplicated volume mount for git sync in scheduler template

[turbaszek]

closes: #12716

Before:

➜ helm install airflow . --namespace airflow --set executor=CeleryExecutor --set airflow_dags_mount_path=/airflow/dags \
  --set dags.persistence.enabled=true \
  --set dags.gitSync.enabled=true \
  --set dags.gitSync.repo=https://github.com/turbaszek/vigilant-giggle \
  --set dags.gitSync.subPath=dags \
  --set defaultAirflowTag=master-python3.7
Error: Deployment.apps "airflow-scheduler" is invalid: spec.template.spec.containers[0].volumeMounts[4].mountPath: Invalid value: "/opt/airflow/dags": must be unique

After:

➜ helm install airflow . --namespace airflow --set executor=CeleryExecutor --set airflow_dags_mount_path=/airflow/dags \
  --set dags.persistence.enabled=true \
  --set dags.gitSync.enabled=true \
  --set dags.gitSync.repo=https://github.com/turbaszek/vigilant-giggle \
  --set defaultAirflowTag=master-python3.7
NAME: airflow
LAST DEPLOYED: Mon Nov 30 12:24:30 2020
NAMESPACE: airflow
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
Thank you for installing Airflow!

Your release is named airflow.
You can now access your dashboard(s) by executing the following command(s) and visiting the corresponding port at localhost in your browser:

Airflow dashboard:        kubectl port-forward svc/airflow-webserver 8080:8080 --namespace airflow
Flower dashboard:         kubectl port-forward svc/airflow-flower 5555:5555 --namespace airflow

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[ashb]

Can you add tests please?

[turbaszek]

Can you add tests please?

Will do, once I figure more change to make it work as there are other problems with PVC

[turbaszek]

Because:

airflow/chart/templates/scheduler/scheduler-deployment.yaml

Lines 203 to 207 in 5e13c37

	{{- if .Values.dags.persistence.enabled }}
	- name: dags
	persistentVolumeClaim:
	claimName: {{ template "airflow_dags_volume_claim" . }}
	{{- else if .Values.dags.gitSync.enabled }}

[turbaszek]

In this way we can deploy just like that - no need to specify anything.