Add info about logging into shell before removing /mnt/data (#16723)

* Add info about logging into shell before removing /mnt/data

details
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- rm -rf should be run after logging into the node shell

* Re-use text from start of the task with small tweaks

content/en/docs/tasks/configure-pod-container/configure-persistent-volume-storage.md

@@ -170,7 +170,9 @@ kubectl delete pvc task-pv-claim
 kubectl delete pv task-pv-volume
 ```
 
-Remove the file:
+Open the shell to the Node in your cluster again (how you open a shell depends on how
+you set up your cluster. For example, if you are using Minikube, you can open a
+shell to your Node by entering `minikube ssh`) and remove the file:
 
 ```shell
 sudo rm -rf /mnt/data