consider using github actions for hugo deployment

[alee]

Deployment from GitHub Actions will likely become the new default soon and we can simplify our github action's dependencies as well by following these steps instead:

https://gohugo.io/hosting-and-deployment/hosting-on-github/

This means we won't have a "built" branch in the repository where the published html lives

https://github.com/openmodelingfoundation/openmodelingfoundation.github.io/commits/main