ios_user purge example (#42904)

* Update ios_user.py

Added an example of purging all users except those listed and admin

* Update ios_user.py

lib/ansible/modules/network/ios/ios_user.py

@@ -121,6 +121,14 @@ EXAMPLES = """
   ios_user:
     purge: yes
 
+- name: remove all users except admin and these listed users
+  ios_user:
+    aggregate:
+      - name: testuser1
+      - name: testuser2
+      - name: testuser3
+    purge: yes
+
 - name: set multiple users to privilege level 15
   ios_user:
     aggregate: