Build tools default to `x64` on `arm64` Windows

[nikwen]

Operating System

Windows 11 on arm64

Expected Behavior

e init testing -i testing --bootstrap will build the arm64 version of Elecron.

Actual Behavior

e init testing -i testing --bootstrap will build the x64 version of Elecron.

To Reproduce

e init testing -i testing --bootstrap on Windows on arm64

Screenshots

Additional Information

[MarshallOfSound]

There aren't arm64 native versions of siso et. al on windows afaik. We could probably override the default behavior by checking os.arch or something in build tools and specifying target_arch explicitly in gn.args.

I'd review a PR for that, should use the config fixer to migrate folks to explicit arch.