update forum access to include check for valid date range

lms/djangoapps/courseware/access.py

@@ -134,8 +134,10 @@ def _has_access_course_desc(user, course, action):
         """
         Can this user access the forums in this course?
         """
-        return (CourseEnrollment.is_enrolled(user, course.id) or \
-            _has_staff_access_to_descriptor(user, course))
+        return (can_load() and \
+            (CourseEnrollment.is_enrolled(user, course.id) or \
+                _has_staff_access_to_descriptor(user, course)
+            ))
 
     def can_enroll():
         """