feat: remove staff access in courses for catalog views (#37)

* feat: remove staff access for catalog views

This is controversial, but simple. To do this in a monkey patch is a bigger task and also with
more work. Is different due the change is in a nested function. Anyway the alternative is to
monkeyPatch the _dispatch method and handle there. But its risky and also that method manage other permission with different ways.

* feat: keep custom test with default behavior

To use you configure the setting: `STAFF_CAN_SEE_IN_CATALOG`

lms/djangoapps/courseware/access.py

@@ -394,7 +394,10 @@ def can_see_in_catalog():
         """
         return (
             _has_catalog_visibility(courselike, CATALOG_VISIBILITY_CATALOG_AND_ABOUT)
-            or _has_staff_access_to_descriptor(user, courselike, courselike.id)
+            or (
+                _has_staff_access_to_descriptor(user, courselike, courselike.id)
+                and getattr(settings, "STAFF_CAN_SEE_IN_CATALOG", True)
+            )
         )
 
     @function_trace('can_see_about_page')