[en] update en docs to use recommended labels

content/en/docs/tasks/run-application/delete-stateful-set.md

@@ -50,10 +50,10 @@ For example:
 kubectl delete -f <file.yaml> --cascade=orphan
 ```
 
-By passing `--cascade=orphan` to `kubectl delete`, the Pods managed by the StatefulSet are left behind even after the StatefulSet object itself is deleted. If the pods have a label `app=myapp`, you can then delete them as follows:
+By passing `--cascade=orphan` to `kubectl delete`, the Pods managed by the StatefulSet are left behind even after the StatefulSet object itself is deleted. If the pods have a label `app.kubernetes.io/name=MyApp`, you can then delete them as follows:
 
 ```shell
-kubectl delete pods -l app=myapp
+kubectl delete pods -l app.kubernetes.io/name=MyApp
 ```
 
 ### Persistent Volumes
@@ -70,13 +70,13 @@ To delete everything in a StatefulSet, including the associated pods, you can ru
 
 ```shell
 grace=$(kubectl get pods <stateful-set-pod> --template '{{.spec.terminationGracePeriodSeconds}}')
-kubectl delete statefulset -l app=myapp
+kubectl delete statefulset -l app.kubernetes.io/name=MyApp
 sleep $grace
-kubectl delete pvc -l app=myapp
+kubectl delete pvc -l app.kubernetes.io/name=MyApp
 
 ```
 
-In the example above, the Pods have the label `app=myapp`; substitute your own label as appropriate.
+In the example above, the Pods have the label `app.kubernetes.io/name=MyApp`; substitute your own label as appropriate.
 
 ### Force deletion of StatefulSet pods