Refactor create_spark_dev function and update API request in startup.py

Author: xuwenyihust

docker/notebook/startup.py

@@ -84,7 +84,7 @@ def __init__(self, spark_session):
         self._spark_session = spark_session
         self.history_server_base_url = "http://localhost:18080"
 
-        self.response = requests.get("http://llocalhost:5002/spark_app/config").json()
+        self.response = requests.get("http://localhost:5002/spark_app/config")
 
     def __getattr__(self, name):
         return getattr(self._spark_session, name)