Update app.py

app.py

@@ -393,7 +393,7 @@ async def join(websocket, key):
     # Register to receive moves from this game.
     connected.add(websocket)
     try:
-        current_directory = f'projects/{key}'
+        current_directory = f'projects/{key}/'
         # Send the first move, in case the first player already played it.
         file_structure = await generate_file_structure(current_directory)
         # Receive and process moves from the second player.