$ git clone -n https://src.fedoraproject.org/rpms/golang-github-eknkc-amber.git /var/lib/mock/f45-build-20123-568/root/chroot_tmpdir/scmroot/golang-github-eknkc-amber
Cloning into '/var/lib/mock/f45-build-20123-568/root/chroot_tmpdir/scmroot/golang-github-eknkc-amber'...
$ git fetch origin 29715adfbffff5a746d4917e10ce5f6f4eadeb69:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-eknkc-amber
 * [new ref]         29715adfbffff5a746d4917e10ce5f6f4eadeb69 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 29715ad Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild