Update app.py

app.py

@@ -125,7 +125,7 @@ def render_message(history):
     <script>
          function scrollToBottom() {
             var chatbox = document.getElementById('chatbox-container');
-            chatbox.scrollTop = chatbox.scrollHeight; 
+            chatbox.scrollTop =- chatbox.scrollHeight; 
         }
         window.onload = function() {
             scrollToBottom();