doc: correct upgrade doc
doc: correct upgrade doc

fixed the missing `v` version in upgrade
doc.

Signed-off-by: Madhu Rajanna <60fbf37a92c2a0908e31296d18dadbec5a4dae17@gmail.com>

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