Tests: fix Solr limit-to-registered-models test

Got lost in commit squashing…

Author: acdha

test_haystack/solr_tests/test_solr_backend.py

@@ -370,7 +370,7 @@ def test_search(self):
         self.assertEqual(self.sb.search('*:*', limit_to_registered_models=False)['hits'], 3)
         self.assertEqual([result.pk for result in self.sb.search('*:*', limit_to_registered_models=False)['results']], ['1', '2', '3'])
 
-        with patch.object(settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', new=False):
+        with patch.object(settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', new=False, create=True):
             self.assertEqual(self.sb.search(''), {'hits': 0, 'results': []})
             self.assertEqual(self.sb.search('*:*')['hits'], 3)
             self.assertEqual([result.pk for result in self.sb.search('*:*')['results']], ['1', '2', '3'])