$ git clone -n https://src.fedoraproject.org/rpms/go-mmproxy.git /var/lib/mock/f45-build-11661-433/root/chroot_tmpdir/scmroot/go-mmproxy
Cloning into '/var/lib/mock/f45-build-11661-433/root/chroot_tmpdir/scmroot/go-mmproxy'...
$ git fetch origin aa05a3d67ce44b01b6532f9973bdce87f2b16df1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/go-mmproxy
 * [new ref]         aa05a3d67ce44b01b6532f9973bdce87f2b16df1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aa05a3d Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild