Add PVC permission to Operator role

[wyangsun]

Add PVC permission to Operator role, so that Spark Operator able to create Driver pod with PVC by follow spark configs:

    spark.kubernetes.driver.volumes.persistentVolumeClaim.checkpointpvc.options.claimName: "driver"
    spark.kubernetes.driver.volumes.persistentVolumeClaim.checkpointpvc.options.storageClass: "gp2"
    spark.kubernetes.driver.volumes.persistentVolumeClaim.checkpointpvc.options.sizeLimit: "50Gi"
    spark.kubernetes.driver.volumes.persistentVolumeClaim.checkpointpvc.mount.path: "/data"
    spark.kubernetes.driver.volumes.persistentVolumeClaim.checkpointpvc.mount.readOnly: "false"

https://spark.apache.org/docs/latest/running-on-kubernetes.html#using-kubernetes-volumes

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[disaster37]

Hi,

any chance to merge it ?

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: wyangsun, yuchaoran2011

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[yuchaoran2011]

/lgtm