CI: move to GitHub actions

[klauer]

Description

• Remove Travis CI Configuration
• Enable GitHub Actions on pcdsutils

Motivation and Context

Result of actions from my fork with this PR branch: https://github.com/klauer/pcdsutils/actions/runs/3878848661

I'm not sure we can get pcdshub/pcdsutils to show Actions checks until the repository contains workflows itself. (I'd be happy to be proved wrong here, though)

[tangkong]

Results speak for themselves, looks good to me.

This might be better addressed in the cookiecutter repo, but are we fully moving away from the run_tests.py file in favor of just running pytest? If so we should change the documentation on the cookiecutter to reflect that. (I don't think I saw that being changed, but also I don't see run_tests.py in there)

[klauer]

This might be better addressed in the cookiecutter repo, but are we fully moving away from the run_tests.py file in favor of just running pytest? If so we should change the documentation on the cookiecutter to reflect that. (I don't think I saw that being changed, but also I don't see run_tests.py in there)

I'm of the opinion that run_tests.py should go away, as I think it's unnecessary boilerplate. We're a team (of course!), though, so we should agree on it first.

I think the existence of the cookiecutter (whether used often or not) is a great place to show off all of our agreed-upon standards in a concrete way that can be replicated elsewhere (and propagated to existing repositories, when feasible)

[tangkong]

I've personally never used run_tests.py, and would be fine seeing it go 👍

[ZLLentz]

Good call on removing these run_tests files, it's good timing to do it

[ZLLentz]

looks good, just have to redirect the workflow url

[klauer]

Merging this and following up with a test PR to verify that actions are really working here (they are on my fork's actions, as above)