$ git clone -n https://src.fedoraproject.org/rpms/signify.git /var/lib/mock/f45-build-35953-700/root/chroot_tmpdir/scmroot/signify
Cloning into '/var/lib/mock/f45-build-35953-700/root/chroot_tmpdir/scmroot/signify'...
$ git fetch origin e46c3261132b0a89ba966bb4101bcfde239f930b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/signify
 * [new ref]         e46c3261132b0a89ba966bb4101bcfde239f930b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e46c326 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild