ci: enable `pybind11` on Windows and macOS builds
This will allow SMTK to test Python from the superbuild bundles that get constructed.
A GitLab update will be applied on May 9th, between 8am and 10am, EDT (UTC-04:00). This site may have intermittent delays during that time.
This will allow SMTK to test Python from the superbuild bundles that get constructed.