$ git clone -n https://src.fedoraproject.org/rpms/rubygem-minitest.git /var/lib/mock/f45-build-35057-693/root/chroot_tmpdir/scmroot/rubygem-minitest
Cloning into '/var/lib/mock/f45-build-35057-693/root/chroot_tmpdir/scmroot/rubygem-minitest'...
$ git fetch origin 231f8f99d152635cb11f1dda0a3f60bc0ec7be63:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-minitest
 * [new ref]         231f8f99d152635cb11f1dda0a3f60bc0ec7be63 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 231f8f9 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild