$ git clone -n https://src.fedoraproject.org/rpms/kscreenlocker.git /var/lib/mock/f40-build-2126210-50780/root/chroot_tmpdir/scmroot/kscreenlocker
Cloning into '/var/lib/mock/f40-build-2126210-50780/root/chroot_tmpdir/scmroot/kscreenlocker'...
$ git fetch origin 7662d578e2eae043202b77a7939df19e98cfe8f5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kscreenlocker
 * [new ref]         7662d578e2eae043202b77a7939df19e98cfe8f5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7662d57 5.91.0