Fixed error introduced when testing patch for 013db6b

Shame on me.

Author: claudep

tests/regressiontests/admin_util/tests.py

@@ -314,7 +314,7 @@ def test_flatten_fieldsets(self):
 
  fieldsets = (
  (None, {
- 'fields': ['url', 'title', ['content', 'sites'])
+ 'fields': ('url', 'title', ['content', 'sites'])
  }),
  )
  self.assertEqual(flatten_fieldsets(fieldsets), ['url', 'title', 'content', 'sites'])