Replace TravisCI with Github Action Workflow

[bensheldon]

TravisCI has gone through a business transition and I think Github Actions, which is free for public repos, is a good alternative.

Note: there is additional contributor documentation that will need to be updated, but I would like to ensure that Github Actions is a viable alternative before doing a broad sweep of process change updates.

[bensheldon]

@assaf @phillbaker would one of you be able to enable Github Actions on this repository, or to provide me admin permissions so that I can enable it? Thank you 🙏

[phillbaker]

I don't have admin access - I think I reached him on twitter actually laster time: https://twitter.com/assaf

[assaf]

It says that all actions are enabled for this repository. I don't see any permission levels, only add/remove contributors.

[bensheldon]

@frostmark I'm going to merge this to the main branch. I think it's possible that GH actions won't kick off until there is a workflow on the main branch.