[3.12] gh-109408: Move Windows builds from Azure Pipelines PR to GitHub Actions (GH-109569)

[miss-islington]

(cherry picked from commit 14cdefa)

Co-authored-by: Hugo van Kemenade hugovk@users.noreply.github.com

• Issue: Move Azure Pipelines CI to GitHub Actions #109408

[ambv]

@Yhg1s this can be landed now as it doesn't invalidate any open PRs and doesn't introduce any new blocking builds:

• Azure Windows builds weren't required to pass to merge PRs before anyway;
• GHA was already running duplicate win32 and x86-64 tests;
• the new Windows ARM64 build on GHA is listed as an allowed failure and skip;
• the remaining Azure job "Ubuntu patchcheck" is left alone.