$ git clone -n https://src.fedoraproject.org/rpms/guile30.git /var/lib/mock/f45-build-13244-447/root/chroot_tmpdir/scmroot/guile30
Cloning into '/var/lib/mock/f45-build-13244-447/root/chroot_tmpdir/scmroot/guile30'...
$ git fetch origin 02e10edb81330f62ddd16d33a3d357dc61852d8c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/guile30
 * [new ref]         02e10edb81330f62ddd16d33a3d357dc61852d8c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 02e10ed Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild