CI: use GitHub Actions to run tests

[Loyalsoldier]

Run tests on macOS, Ubuntu and Windows with latest Go release using GitHub Actions triggered by:

• push and pull request event
• changes of files **/*.go, go.mod and go.sum

[bigangryrobot]

This looks great. My only suggestion is that we look at the triggers a bit, as I would generally recommend using branch and tag based actions over path based

    paths:
      - "**/*.go"
      - "go.mod"
      - "go.sum"
      - ".github/workflows/test.yml"

[Loyalsoldier]

@bigangryrobot Yeah, the test is triggered by push and pull request event on main branch, and the paths are just used to filter file changes that do not need to run the test, e.g. document changes.