Added examples for WAF create and update

Author: briantkim-msft

src/nginx/azext_nginx/_help.py

@@ -11,9 +11,17 @@
 from knack.help_files import helps  # pylint: disable=unused-import
 
 helps['nginx deployment waf-policy create'] = """
-    type: group
-    short-summary: Commands to manage Nginx Deployment WAF Policies.
+    type: command
+    short-summary: Command to create an Nginx Deployment WAF Policy.
     examples:
         - name: Create a WAF policy for a Nginx deployment
           text: az nginx deployment waf-policy create --name mypolicyname --deployment-name mydeploymentname --resource-group myresourcegroupname --filepath /path/to/my/policy.json --content mycontentfileinbase64encoding
 """
+
+helps['nginx deployment waf-policy update'] = """
+    type: command
+    short-summary: Command to update an Nginx Deployment WAF Policy.
+    examples:
+        - name: Update a WAF policy for a Nginx deployment
+          text: az nginx deployment waf-policy update --name mypolicyname --deployment-name mydeploymentname --resource-group myresourcegroupname --filepath /path/to/my/policy.json --content mycontentfileinbase64encoding
+"""