On October 20th, 2020, the default Xcode version of GitHub Actions was switched from 11.7 to 12.0.1, breaking the CI. This PR explicitly sets the Xcode version to revert is back to 11.7 and avoid this from happening in the future.
I made a stupid mistake not realizing the -version parameter disabled the build aside from printing the version. The CI stopped working before october 20th, so the CI issue is something else.
On October 20th, 2020, the default Xcode version of GitHub Actions was switched from 11.7 to 12.0.1, breaking the CI. This PR explicitly sets the Xcode version to revert is back to 11.7 and avoid this from happening in the future.
See also: https://github.com/actions/virtual-environments/issues/1712
The macOS version is also fixed to avoid similar issues in the future (
latest
=10.15
right now).