Support extraVolumeMounts and extraVolumes for deployment in templates

[romikoops]

Many charts have it. In my case, it will help me to mount a sharable folder and use it with MH_MAILDIR_PATH for multi replicas sync

[romikoops]

just an example:

       extraVolumeMounts:
         - name: "shared-data"
            mountPath: "/data"
        extraVolumes:
          - name: "shared-data"
            persistentVolumeClaim: 
              claimName: XXX

[github-actions]

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