Migrate to GitHub Actions

[laike9m]

Many automations only exist in GitHub Actions, like this one: https://github.com/marketplace/actions/detect-and-tag-new-version

We can do this with the PDM migration as PDM has good support for GitHub Actions, and we can just start a fresh setup, and gradually migrate azure pipeline settings to it.

https://github.com/pdm-project/setup-pdm

[laike9m]

Needs to update the dev doc as well.