Surprising behavior of 0.53.0 build on Windows

[cputnam-gsbs]

Building russh 0.53.0 fails on Windows with toolchain stable-x86_64-pc-windows-msvc and either default or no features.

With default features, the build fails on a custom build script for aws-lc-rs. The error sugguests that aws-lc-rs expects NASM and cmake, neither of which are present by default on Windows.

russhbuild-with-default-features.txt

With no default features, the build fails with missing symbols.

russhbuild-no-default-features.txt

The release notes for 0.53.0 suggest that if we don't want aws-lc-rs, that we should use feature "ring". Yep, that works, but this surprising behavior. I understand that we can't control features per target, but if that's the case then in my amature opinion the right thing to do is to make "ring" a default feature and make aws-lc-rs opt-in.