updating the cephcsi image to v3.8.0
release and also removing support for
3.6.0 as its deprecated and not supported
any more.
More details at
https://github.com/ceph/ceph-csi/releases/tag/v3.8.0
and https://github.com/ceph/ceph-csi/tree/release-v3.8
\#ceph-csi-container-images-and-release-compatibility
fixes #11688
Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
(cherry picked from commit b01180580c)