docs: Create New Document for KubeVirt VM Backup and Restore, Update Exiting Docs

Signed-off-by: Bala Harish <161304963+balaharish7@users.noreply.github.com>

Author: balaharish7

docs/versioned_sidebars/version-4.2.x-sidebars.json

@@ -825,3 +825,4 @@
       }
     }
   ]
+}