$ git clone -n https://src.fedoraproject.org/rpms/kscreenlocker.git /var/lib/mock/f42-build-862455-170817/root/chroot_tmpdir/scmroot/kscreenlocker
Cloning into '/var/lib/mock/f42-build-862455-170817/root/chroot_tmpdir/scmroot/kscreenlocker'...
$ git fetch origin 723c35ff81e8ccc3211c6561e88117b285b8612b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kscreenlocker
 * [new ref]         723c35ff81e8ccc3211c6561e88117b285b8612b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 723c35f 6.2.4