Update app.py

app.py

@@ -223,7 +223,7 @@ htmlTemplate = f"""
     <script src="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.0.0/js/all.min.js" integrity="sha512-yFjZbTYRCJodnuyGlsKamNE/LlEaEA/3uWCGാരി7eIq7jWqVl3J8jL/kof/tfu9Xqzh/y/VM5sJd/tq5iEew==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>
 
   <script>
-    const username = '{{username}}';
+    const username = '{USERNAME}';
 
     async function fetchInstances() {{
       try {{
@@ -479,4 +479,3 @@ def stream_metrics(username, instance_id):
 
 if __name__ == '__main__':
     app.run(debug=True, host='0.0.0.0', port=7860)
-