build: Produce a Windows arm64 binary

[xiehan]

I'm not familiar enough with platform-specific differences to know whether our ability to produce a build is enough confidence that this will work, or whether we need to do manual testing to verify. We did unfortunately figure out that our existing E2E tests won't work for this platform, so any verification will need to be manual.

Fixes #32719

Target Release

1.10.x, or we could backport to 1.9.x, this is relatively flexible

Draft CHANGELOG entry

NEW FEATURES

• We now produce builds for Windows ARM64

[apparentlymart]

I expect there's probably context here that I'm not aware of and so what I'm about to say might be redundant, but just to make sure:

In the past when we've introduced new officially-supported platforms (darwin_arm64 being the most recent example) we've asked the developers of the official providers to lead first and produce at least one or two provider releases that support the new platform.

If Terraform CLI/Core were to go first then we'd be publishing something that's more-or-less useless, because a Terraform Core without any providers doesn't do anything of value. I would expect it to cause folks to open bug reports in this repository saying that provider installation failed for them, and that to then create indirect pressure for provider developers to rush to make new releases supporting the new platform.

I mention this only because none of the official providers I quickly checked seems to be offering a windows_arm64 build for its latest release. If there's already a plan to make that happen before the first Core release supporting that platform, or if there's some different plan to deliver this which bypasses the need for providers to go first, then of course please ignore me. 😀

[crw]

This is excellent context, thank you!