$ git clone -n https://src.fedoraproject.org/rpms/perl-Alien-Libxml2.git /var/lib/mock/f45-build-21635-587/root/chroot_tmpdir/scmroot/perl-Alien-Libxml2
Cloning into '/var/lib/mock/f45-build-21635-587/root/chroot_tmpdir/scmroot/perl-Alien-Libxml2'...
$ git fetch origin 3a27a925c10f2f33afc0f469b12773872ff3c5e5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Alien-Libxml2
 * [new ref]         3a27a925c10f2f33afc0f469b12773872ff3c5e5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3a27a92 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild