CI: build also on Windows

[mhujer]

Let's build also on Windows to prevent issues similar to #204 in the future.

[stof]

Looks like your git config --global core.autocrlf false trick does not work properly here. It still have a test failure where the expected output uses \r\n, which is not the case in the source code. I think you also need git config --global core.eol lf

[mhujer]

@stof Yes, that fixes it 👍 (I've amended the commit and verified the build in my fork)