fix: load setting error when some option not exist

Author: chunlampang

libs/ktem/ktem/pages/settings.py

@@ -362,7 +362,7 @@ def load_setting(self, user_id=None):
                 settings = result[0].setting
 
         output = [settings]
-        output += tuple(settings[name] for name in self.component_names())
+        output += tuple(settings.get(name) for name in self.component_names())
         return output
 
     def save_setting(self, user_id: int, *args):