Remove mocked has_dynamic_children method - un-needed after vertical

block conversion.

lms/djangoapps/courseware/tests/test_entrance_exam.py

@@ -246,7 +246,6 @@ class EntranceExamTestCases(LoginEnrollmentTestCase, ModuleStoreTestCase):
             ]
         )
 
-    @mock.patch('xmodule.x_module.XModuleMixin.has_dynamic_children', mock.Mock(return_value='True'))
     def test_view_redirect_if_entrance_exam_required(self):
         """
         Unit Test: if entrance exam is required. Should return a redirect.