OSSM-9037 Show oc label command in Performing RevisionBased update procedure

Author: gwynnemonahan

modules/ossm-performing-revisionbased-update.adoc

@@ -34,11 +34,16 @@ The {SMProductShortName} Operator deploys a new version of the control plane alo
 $ oc get istiorevisions
 ----
 
-. Move the workloads to the new control plane by updating the `istio.io/rev` label on the application namespace or the pods to the revision name of the new control plane.
+. Move the workloads to the new control plane by updating the `istio.io/rev` label on the application namespace by running the following command:
++
+[source,terminal]
+----
+$ oc label namespace <namespace_name> istio.io/rev=<new_revision_name> --overwrite
+----
 
 . Restart the application workloads so that the new version of the sidecar gets injected.
 +
 [source,terminal]
 ----
 $ oc rollout restart deployment <deployment_name>
-----
+----