Enabled course id clash command tests

cms/djangoapps/contentstore/management/commands/tests/test_course_id_clash.py

@@ -3,9 +3,7 @@ from StringIO import StringIO
 from django.test import TestCase
 from django.core.management import call_command
 from xmodule.modulestore.tests.factories import CourseFactory
-from nose.plugins.skip import SkipTest
 
-@SkipTest
 class ClashIdTestCase(TestCase):
     """
     Test for course_id_clash.