$ git clone -n https://src.fedoraproject.org/rpms/git-up.git /var/lib/mock/f45-build-11092-427/root/chroot_tmpdir/scmroot/git-up
Cloning into '/var/lib/mock/f45-build-11092-427/root/chroot_tmpdir/scmroot/git-up'...
$ git fetch origin 2a1ae1ecce856b7098ed7016eda1a40092c78307:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/git-up
 * [new ref]         2a1ae1ecce856b7098ed7016eda1a40092c78307 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2a1ae1e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild