do not set _config key of settings in _prepare_config, it is achieved in _prepare_settings

Author: echarles

jupyter_server/extension/application.py

@@ -216,7 +216,6 @@ def _prepare_config(self):
         traits = self.class_own_traits().keys()
         self.extension_config = Config({t: getattr(self, t) for t in traits})
         self.serverapp.web_app.settings['{}_config'.format(self.extension_name)] = self.extension_config
-        self.settings['{}_config'.format(self.extension_name)] = self.extension_config
 
     def _prepare_settings(self):
         # Make webapp settings accessible to initialize_settings method