Workshop in ADASS

We have done quite a few in AAS but those are introductory and aimed at *users*. According to https://astropy-report.orgmycology.com/sections/community_recommendations#workshops , there might be a need for workshop that targets new potential contributors in ADASS.

*I think we could hold contributor workshops or Github workshops at more technical meetings like ADASS.*

The issue names no files, tests, or entry points. Start by reviewing the linked community recommendations and the existing AAS workshop materials, then define the ADASS audience, format, and scope; done means an agreed proposal for a contributor or GitHub workshop.

Written by the indexing model from the issue text.