Add message for setting course goal.

LEARNER-2307

openedx/core/lib/api/permissions.py

@@ -166,4 +166,5 @@ class IsStaffOrOwner(permissions.BasePermission):
         return user.is_staff \
             or (user.username == request.GET.get('username')) \
             or (user.username == getattr(request, 'data', {}).get('username')) \
+            or (user.username == getattr(request, 'data', {}).get('user')) \
             or (user.username == getattr(view, 'kwargs', {}).get('username'))