$ git clone -n https://src.fedoraproject.org/rpms/libass.git /var/lib/mock/f45-build-15846-480/root/chroot_tmpdir/scmroot/libass
Cloning into '/var/lib/mock/f45-build-15846-480/root/chroot_tmpdir/scmroot/libass'...
$ git fetch origin 9eb6670fef2233fab7dad0a1b8e7abfd970beafb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libass
 * [new ref]         9eb6670fef2233fab7dad0a1b8e7abfd970beafb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9eb6670 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild