Publish to GHCR

[joryirving]

Is your feature request related to a problem? Please describe. Dockerhub has aggressive pull rate limits,

Describe the solution you'd like It would be awesome if you could push the image to Github Container Registry (GHCR) as well.

Additional context Dockerhub was one of the best years ago... GHCR is completely free for open source projects. It's also nice in that it integrates into your repo under the packages section.