Nightly builds with MacOS started failing again
due to an upgrade of the default virtual environment
that now uses Python 3.8
This makes us hit #14102 and every build fails. This
commit should be reverted along with the fix to #14102.
* MacOS build tests
- Run on PR that modify the YAML file of the workflow
- Don't clone Spack, since we are in the Spack repo now
* Try to add opengl to configuration to build jupyter
* fixup
