$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-File.git /var/lib/mock/f45-build-26673-618/root/chroot_tmpdir/scmroot/perl-Test-File
Cloning into '/var/lib/mock/f45-build-26673-618/root/chroot_tmpdir/scmroot/perl-Test-File'...
$ git fetch origin b287b31f4ebf59a33485906ae78c83dda4add047:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-File
 * [new ref]         b287b31f4ebf59a33485906ae78c83dda4add047 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b287b31 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild