Custom format constrains on Schema wrapper method

[georgesofianosgr]

Hello, we are using Apollo 4 plugin to use constrains in production.
For our tests we are calling graphQL directly on the schema so we use the Schema wrapper method.
Are custom format constrains not supported with this method ? There is no example of using it with schema wrapper method.

[steffenkoenig]

@georgesofianosgr I just had the same requirements and have added this with #297