$ git clone -n https://src.fedoraproject.org/rpms/libcss.git /var/lib/mock/f45-build-15969-481/root/chroot_tmpdir/scmroot/libcss
Cloning into '/var/lib/mock/f45-build-15969-481/root/chroot_tmpdir/scmroot/libcss'...
$ git fetch origin 47d161c7ccf5e96ffeadd46da0c285f971ada0ce:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libcss
 * [new ref]         47d161c7ccf5e96ffeadd46da0c285f971ada0ce -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 47d161c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild