Add no-config variant of pandas_hello_world
Adding a no-config variant of the pandas_hello_world so that we don't have to introduce
the config system interaction with the runtime type system in the very first demo.
Test Plan: Run it in dagit
Reviewers: #ft, natekupp
Reviewed By: #ft, natekupp
Differential Revision: https://dagster.phacility.com/D718