NCLU - Add example: Changing the hostname and committing on Cumulus Linux (#42872)

* Add example to change the hostname and commit on Cumulus Linux

* Modify phrasing a bit

lib/ansible/modules/network/cumulus/nclu.py

@@ -64,6 +64,12 @@ EXAMPLES = '''
         - add int swp1
         - add int swp2
 
+- name: Modify hostname to Cumulus-1 and commit the change
+  nclu:
+    commands:
+        - add hostname Cumulus-1
+    commit: true
+
 - name: Add 48 interfaces and commit the change.
   nclu:
     template: |