Fix feature import test.

Author: WaVEV

django_mongodb/features.py

@@ -44,7 +44,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         # Regex lookup doesn't work on non-string fields.
         "lookup.tests.LookupTests.test_regex_non_string",
         # Substr not implemented.
-        "lookup.tests.LookupTests.test_pattern_lookups_with_substr"
+        "lookup.tests.LookupTests.test_pattern_lookups_with_substr",
         # Querying ObjectID with string doesn't work.
         "lookup.tests.LookupTests.test_lookup_int_as_str",
         # Regex lookup doesn't work on json fields.