fix syntax error

chat_application/main.py

@@ -437,7 +437,7 @@ def ask_bot_round(room_id):
 def backup_mongo(time):
     while (True):
         token = os.getenv("HF_TOKEN")
-        handler = dataset_handler(token , 'huggingFaceData')
+        handler = datasetHandler(token , 'huggingFaceData')
         handler.dump_db()
         socketio.sleep(time)