Adjust test for ListField(IntegerField)

The `maximum` is valid here within the schema but it was not
previously being included because we were not copying over the
entire schema for the generated `IntegerField` previously.

tests/schemas/test_openapi.py

@@ -51,7 +51,7 @@ def test_list_field_mapping(self):
             (serializers.ListField(child=serializers.FloatField()), {'items': {'type': 'number'}, 'type': 'array'}),
             (serializers.ListField(child=serializers.CharField()), {'items': {'type': 'string'}, 'type': 'array'}),
             (serializers.ListField(child=serializers.IntegerField(max_value=4294967295)),
-             {'items': {'type': 'integer', 'format': 'int64'}, 'type': 'array'}),
+             {'items': {'type': 'integer', 'maximum': 4294967295, 'format': 'int64'}, 'type': 'array'}),
             (serializers.ListField(child=serializers.ChoiceField(choices=[('a', 'Choice A'), ('b', 'Choice B')])),
              {'items': {'enum': ['a', 'b']}, 'type': 'array'}),
             (serializers.IntegerField(min_value=2147483648),