Update to dataclass-wizard version to support Union types while checking unmatched keys

Previously `dataclass-wizard` had a bug that meant we couldn't both use `Union` types in the config dataclasses while at the same time checking that all keys in the loaded yaml-file match the config dataclasses. This bug has now been fixed and we should update our dependency: https://github.com/rnag/dataclass-wizard/issues/137