Migrate to centralized GitHub workflows

[nicholasmhughes]

What does this PR do?

This PR implements calls to "reusable workflows" housed in the salt-extensions/central-artifacts repository. This should allow us to more easily keep GitHub Actions up-to-date without requiring PRs to be opened for every extension. The proposed workflow YAML can be viewed in the central-artifacts repository, but for posterity the Push/PR and Release pipelines look something like this:

• Push/PR
  • Automatic Processes (kicked off by push/PR)
    • Run pre-commit checks
    • Run test matrix for Linux, Windows, and macOS
    • Run doc build
• Tag Creation
  • Manual Processes
    • Create a PR to update the CHANGELOG with towncrier
    • Create a tag at the merged commit above for the release version using semantic versioning (i.e. v1.0.0)
  • Automatic Processes (kicked off by tag creation)
    • Run pre-commit checks
    • Run test matrix for Linux, Windows, and macOS
    • Run doc build
    • Build the package
    • Release the package to Test PyPi (uses the saltext-community account)
    • Create a GitHub Release for the package
    • Release the package to PyPi (uses the saltext-community account)

Commits signed with GPG?

Yes

Please review Salt's Contributing Guide for best practices.

See GitHub's page on GPG signing for more information about signing commits with GPG.

[lkubb]

Thanks for doing all this work, very happy about more centralization in the salt-extensions org!

Do you have a solution handy for the Vault setup or should I look into it?

Also, the pre-commit workflow is failing, maybe this repo's secrets need to be updated (?).

[nicholasmhughes]

I probably should've put this in Draft status... but here we are. Pre-commit is failing due to a problem with getting changed files via Action. I think it's because I indiscriminately updated the action version, and there's probably an output format change... Looking into it later today.

[nicholasmhughes]

Ok. All fixed up. Let me know if you think this will work for our needs.

[lkubb]

Love it, thank you very much! 👍 Now we're just missing readthedocs for salt-extensions, then everything should be neat.

I will make this enhancement an optional part of the copier template as well.

Sorry for taking so long to review btw, somehow missed the update.

Have a happy new year! 🚀