Deployment behaves better when a node gets disconnected
from the rest of the cluster - new provisioner leader
is elected in ~15 seconds, while it may take up to
5 minutes for StatefulSet to start a new replica.
if kube version is 1.13.x deploy provisioner as statefulset.
if kube version is higher than 1.14+ deploy provisioner
as deployment.
Refer: kubernetes-csi/external-provisioner@52d1fbc
Refer: ceph/ceph-csi#497
Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>