Use Pydantic model_dump in serializer

[baumgold]

Attempts to fix #754 by using the Pydantic serializer when serializing a model via the CLI

[kschwab]

+@hramezani

@baumgold this is a good idea, thanks for the PR. We just need to make sure to maintain backwards compatibility. Can you add a bool kwarg (use_serializers?) to the serialize method with the default set to False. Then you can just make dumped_model an empty dictionary if flag is not set and update dumped_field to:

dumped_field = dumped_model.get(field_name, model_default)

You will also need to add some tests.