kubectl describe <kind> work with no arguments

Add describe_resource_assert to test describe <kind> with no object arg

docs/man/man1/kubectl-describe.1

@@ -159,6 +159,9 @@ $ kubectl describe pods/nginx
 // Describe a pod using the data in pod.json.
 $ kubectl describe \-f pod.json
 
+// Describe all pods
+$ kubectl describe pods
+
 // Describe pods by label name=myLabel
 $ kubectl describe po \-l name=myLabel