Fix cascade option value (bregman-arie#330)

--cascade=false is deprecated (boolean value) and can be replaced with --cascade=orphan

Author: chimons

topics/kubernetes/solutions/replicaset_02_solution.md

@@ -39,7 +39,7 @@ kubectl get rs
 3. Remove the ReplicaSet but NOT the pods it created
 
 ```
-kubectl delete -f rs.yaml --cascade=false
+kubectl delete -f rs.yaml --cascade=orphan
 ```
 
 4. Verify you've deleted the ReplicaSet but the Pods are still running