$ git clone -n https://src.fedoraproject.org/rpms/xfmpc.git /var/lib/mock/f45-build-38898-730/root/chroot_tmpdir/scmroot/xfmpc
Cloning into '/var/lib/mock/f45-build-38898-730/root/chroot_tmpdir/scmroot/xfmpc'...
$ git fetch origin dd015feabe9563e6400d1c860a7bcfe094f52d54:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xfmpc
 * [new ref]         dd015feabe9563e6400d1c860a7bcfe094f52d54 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dd015fe Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild