Consider migration CI for Windows into GitHub Actions

[yhatt]

Marp team's primary CI won't change from CircleCI, but I think a new bulit-in CI/CD for GitHub Actions is easier to maintain than Azure Pipelines, that is the current secondary CI for Marp team for running tests and builds in Windows environment.

In fact, GitHub Actions is using Azure Pipelines backend.

ToDo

• Wait until enabled GitHub Actions for Marp team (-Nov, 13)
• Set up GitHub Actions
  • Test in Windows environment
  • Create Windows binary via pkg
  • Upload packaged asset of standalone binary for Windows to GitHub release page

CircleCI has started supporting Windows environment too. It provides only to user of performance plan, and not yet provided free plan to OSS projects. We might re-migrate to CircleCI when Windows environment in CircleCI could use in OSS project in future.