The Windows ARM64 builders on Azure have replaced the Windows ARM64
builders on AWS by now. Remove unused environment configuration; we
can bring it back or look it up in history if needed.
Updates golang/go#53541.
Updates golang/go#42604.
Updates golang/go#57408.
Change-Id: I080e4f5c53712c0470332a7d26d00c939136e57c
Reviewed-on: https://go-review.googlesource.com/c/build/+/462655
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
b263a02021