Migrate CI to GitHub actions

[JoelSpeed]

I would like to see code coverage, linting and testing status checks for all PRs to the project. Currently with Travis, we just get the one build check. Also, because we put the code coverage ID in a travis secret, this doesn't work on PRs from forks of the repos

I think if we move to GitHub actions, we get more information from the events that trigger builds that might allow us to create conditional statements that allow our actions to run and perform code coverage only when being PR'd to the OAuth2 Proxy. What we should avoid is getting code coverage reports whenever anything is pushed to any branch of any fork.

Likewise our CodeQL action is also broken and only works for pushes to this repository and not forks. It would be good to fix that too.

[shinebayar-g]

I can migrate your travis configuration to github actions if you want

[JoelSpeed]

If you have experience with actions, that would be appreciated

[github-actions]

This issue has been inactive for 60 days. If the issue is still relevant please comment to re-activate the issue. If no action is taken within 7 days, the issue will be marked closed.

[JoelSpeed]

I would still like to see this done

[shinebayar-g]

Opened PR

[JoelSpeed]

Just had a look at the PR, looks like a great start, thanks!