fixup! fix: adjust studio_grading_url to use the correct URL

Author: dwong2708

lms/djangoapps/instructor/tests/test_api_v2.py

@@ -118,7 +118,7 @@ def _get_url(self, course_id=None):
             course_id = str(self.course_key)
         return reverse('instructor_api_v2:course_metadata', kwargs={'course_id': course_id})
 
-    @override_settings(COURSE_AUTHORING_MICROFRONTEND_URL='http://localhost:2001/authoring')
+    @override_settings(COURSE_AUTHORING_MICROFRONTEND_URL='http://localhost:2001')
     def test_get_course_metadata_as_instructor(self):
         """
         Test that an instructor can retrieve comprehensive course metadata.

lms/djangoapps/instructor/views/serializers_v2.py

@@ -458,10 +458,10 @@ def get_studio_grading_url(self, data):
         mfe_base_url = configuration_helpers.get_value_for_org(
             course_key.org,
             'COURSE_AUTHORING_MICROFRONTEND_URL',
-            settings.COURSE_AUTHORING_MICROFRONTEND_URL
+            getattr(settings, 'COURSE_AUTHORING_MICROFRONTEND_URL', None)
         )
         if mfe_base_url:
-            return f'{mfe_base_url}/course/{course_key}/settings/grading'
+            return f'{mfe_base_url}/authoring/course/{course_key}/settings/grading'
         return None
 
     def get_disable_buttons(self, data):