$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-Script.git /var/lib/mock/f45-build-26847-619/root/chroot_tmpdir/scmroot/perl-Test-Script
Cloning into '/var/lib/mock/f45-build-26847-619/root/chroot_tmpdir/scmroot/perl-Test-Script'...
$ git fetch origin 166f32e3edaeb233839b57f2681b9bf463af6704:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-Script
 * [new ref]         166f32e3edaeb233839b57f2681b9bf463af6704 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 166f32e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild