x/build: add Windows 11 builders

[prattmic]

The Windows builders all use Windows 10 (22H2) today. We should probably add Windows 11 builders, since most users likely use Windows 11.

Note that starlark/common/envs/chrome.star already defines Windows 11 images alongside the Windows 10 ones that we currently use.

cc @golang/release

[Musteab]

Hi! I’d like to work on this.

Before starting, could you confirm the intended initial scope: should the change add both Windows 11 amd64 and 386 builders mirroring the existing Windows 10 builders, or start with amd64 only?

I plan to reuse the existing Windows 11 image definitions and update the builder configuration and relevant tests.