DeprecationWarning from jsonschema

The problem here is that https://community-tc.services.mozilla.com/schemas/common/metaschema.json isn't a known metaschema, and jsonschema doesn't try to resolve $ref by default.

ci/tc/tests/test_valid.py:93: in test_verify_payload
    validate(instance=task_data, schema=create_task_schema)
.tox/py311/lib/python3.11/site-packages/jsonschema/validators.py:1115: in validate
    cls = validator_for(schema)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

schema = {'$id': 'https://community-tc.services.mozilla.com/schemas/queue/v1/create-task-request.json#', '$schema': 'https://co...n/metaschema.json#', 'additionalProperties': False, 'description': 'Definition of a task that can be scheduled\n', ...}
default = <unset>

    def validator_for(schema, default=_UNSET):
        """
        Retrieve the validator class appropriate for validating the given schema.
    
        Uses the :kw:`$schema` keyword that should be present in the given
        schema to look up the appropriate validator class.
    
        Arguments:
    
            schema (collections.abc.Mapping or bool):
    
                the schema to look at
    
            default:
    
                the default to return if the appropriate validator class
                cannot be determined.
    
                If unprovided, the default is to return the latest supported
                draft.
        """
    
        DefaultValidator = _LATEST_VERSION if default is _UNSET else default
    
        if schema is True or schema is False or "$schema" not in schema:
            return DefaultValidator
        if schema["$schema"] not in _META_SCHEMAS:
            if default is _UNSET:
>               warn(
                    (
                        "The metaschema specified by $schema was not found. "
                        "Using the latest draft to validate, but this will raise "
                        "an error in the future."
                    ),
                    DeprecationWarning,
                    stacklevel=2,
                )
E               DeprecationWarning: The metaschema specified by $schema was not found. Using the latest draft to validate, but this will raise an error in the future.

Start with ci/tc/tests/test_valid.py:93 and the create_task_schema definition, then run test_verify_payload to reproduce the jsonschema warning. Trace how the schema and its $schema reference are loaded; done means the test still validates the payload without emitting the reported DeprecationWarning.