Add skips for composite_pk tests

Author: timgraham

django_mongodb_backend/features.py

@@ -533,8 +533,18 @@ def django_test_expected_failures(self):
  "foreign_object.test_tuple_lookups.TupleLookupsTests",
  },
  "ColPairs is not supported.": {
- # 'ColPairs' object has no attribute 'as_mql'
  "auth_tests.test_views.CustomUserCompositePrimaryKeyPasswordResetTest",
+ "composite_pk.test_aggregate.CompositePKAggregateTests",
+ "composite_pk.test_create.CompositePKCreateTests",
+ "composite_pk.test_delete.CompositePKDeleteTests",
+ "composite_pk.test_filter.CompositePKFilterTests",
+ "composite_pk.test_get.CompositePKGetTests",
+ "composite_pk.test_models.CompositePKModelsTests",
+ "composite_pk.test_order_by.CompositePKOrderByTests",
+ "composite_pk.test_update.CompositePKUpdateTests",
+ "composite_pk.test_values.CompositePKValuesTests",
+ "composite_pk.tests.CompositePKTests",
+ "composite_pk.tests.CompositePKFixturesTests",
  },
  "Custom lookups are not supported.": {
  "custom_lookups.tests.BilateralTransformTests",