$ git clone -n https://src.fedoraproject.org/rpms/lighttpd.git /var/lib/mock/f40-build-791787-137740/root/chroot_tmpdir/scmroot/lighttpd
Cloning into '/var/lib/mock/f40-build-791787-137740/root/chroot_tmpdir/scmroot/lighttpd'...
$ git fetch origin f3f8ec8d35760057aab820648dc3905e285126b4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lighttpd
 * [new ref]         f3f8ec8d35760057aab820648dc3905e285126b4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f3f8ec8 1.4.74