$ git clone -n https://src.fedoraproject.org/rpms/FlightCrew.git /var/lib/mock/f42-build-862898-171231/root/chroot_tmpdir/scmroot/FlightCrew
Cloning into '/var/lib/mock/f42-build-862898-171231/root/chroot_tmpdir/scmroot/FlightCrew'...
$ git fetch origin 9225aeb845646d6ff587220ed65a58fced29da4b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/FlightCrew
 * [new ref]         9225aeb845646d6ff587220ed65a58fced29da4b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9225aeb Rebuild for xerces-c 3.3