Update templates/chat.html

templates/chat.html

@@ -7,7 +7,7 @@
   <input id="msg" autocomplete="off"><button id="send">Send</button>
   <button id="leave">Leave</button>
 
-  <script src="//cdnjs.cloudflare.com/ajax/libs/socket.io/4.6.1/socket.io.min.js"></script>
+  <script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/4.8.1/socket.io.js"></script>
   <script src="/static/chat.js"></script>
 </body>
 </html>