e2e: add e2e for snapshot retention fetaure.
e2e: add e2e for snapshot retention fetaure.

Added e2e for snapshot retention feature.

Signed-off-by: Mudit Agarwal <e5356c34e3b3b8ef2f9750bb431df6fcd5e2fa6e@redhat.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi