Revert "Bulk-reads and Request caching in Course Grade Report"

This reverts commit 16e9636513.

common/djangoapps/course_modes/tests/test_models.py

@@ -16,7 +16,7 @@ from opaque_keys.edx.locator import CourseLocator
 import pytz
 
 from course_modes.helpers import enrollment_mode_display
-from course_modes.models import CourseMode, Mode, invalidate_course_mode_cache
+from course_modes.models import CourseMode, Mode
 from course_modes.tests.factories import CourseModeFactory
 
 
@@ -31,9 +31,6 @@ class CourseModeModelTest(TestCase):
         self.course_key = SlashSeparatedCourseKey('Test', 'TestCourse', 'TestCourseRun')
         CourseMode.objects.all().delete()
 
-    def tearDown(self):
-        invalidate_course_mode_cache(sender=None)
-
     def create_mode(
             self,
             mode_slug,