ci: Add initial GHA

[chtruong814]

• Add initial GHA to lint and run unit tests as well as release steps, copying over similar steps from other repos.
• "Unit tests" only run on Github runner for now. We can replace with GPU runners when we are running real tests.
• We will want to replace _placeholder throughout these files when we formally update the name
• Commenting out the build test publish step for now since likely requires some setup on test pypi first

[ko3n1g]

Thank you for this initial setup, it looks great! I left some suggestions and questions.

[ko3n1g]

Suggested change

	A helpful guide on on how to craft a minimal bug report http://matthewrocklin.com/blog/work/2018/02/28/minimal-bug-reports.
	A helpful guide on on how to craft a minimal bug report http://matthewrocklin.com/blog/work/2018/02/28/minimal-bug-reports.

[ko3n1g]

While this would be great in theory, it would require a necessary change of our build-test-publish-wheel workflow: This pushes to (test-) pypi with each call. This easily fills up the pypi repository and at some point pypi will reject wheels. It is unclear so far, how to clean up old wheels.

For this reason, this workflow commonly runs only on push to main.

[ko3n1g]

Suggested change

	group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
	group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}-${{ github.event.label.name || 'main' }}

A small quality of life hack: This will prevent the unintuitive behavior where attaching any label kills the ongoing workflow.

[chtruong814]

@ko3n1g thanks for the review. I updated based on the feedback. Please take another look when you have time.