Windows builds run pytest with win32 despite setup-miniconda architecture reporting x64

[Carl Thomé]

This could very well be a user error on my part but trying to figure out why GHA workflows on windows-latest (which should be x64 machines) is getting a possible integer overflow, while ubuntu-latest and macos-latest behave nicely.

setup-miniconda specifies architecture: x64 yet pytest reports running platform win32

Example:

• https://github.com/craffel/mir_eval/actions/runs/5283770085/jobs/9560441233?pr=356#step:4:10
• https://github.com/craffel/mir_eval/actions/runs/5283770085/jobs/9560441233?pr=356#step:6:9