Pull Request Checklist

• Fixes Arguments mapping is very verbose depending on use case #922
• Tests added
• Documentation/examples added
• Good commit messages and/or PR title

Description of PR
This PR makes it possible to subclass Input and Output for the new decorators in HEP0001, and then pass an output from a script template call directly into the next step or task. i.e. instead of

@w.dag()
def my_dag():
    output_task = give_output()
    take_input(
        PassthroughIO(
            my_str=output_task.my_str,
            my_int=output_task.my_int,
            my_artifact=output_task.my_artifact,
        )
    )

you can do

@w.dag()
def my_dag():
    output_task = give_output()
    take_input(output_task)

Note this functionality is limited to script-decorated functions only for now, as other template types would need an even more involved approach where this code had already become complex enough, as we are reconstructing an Output from a step or task object.