$ git clone -n https://src.fedoraproject.org/rpms/grfcodec.git /var/lib/mock/f45-build-13033-446/root/chroot_tmpdir/scmroot/grfcodec
Cloning into '/var/lib/mock/f45-build-13033-446/root/chroot_tmpdir/scmroot/grfcodec'...
$ git fetch origin 9430f2501b397430ae34e0dc9c7fc385e46a4162:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/grfcodec
 * [new ref]         9430f2501b397430ae34e0dc9c7fc385e46a4162 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9430f25 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild