$ git clone -n https://src.fedoraproject.org/rpms/ghc-filepattern.git /var/lib/mock/f41-build-838894-159867/root/chroot_tmpdir/scmroot/ghc-filepattern
Cloning into '/var/lib/mock/f41-build-838894-159867/root/chroot_tmpdir/scmroot/ghc-filepattern'...
$ git fetch origin d9143c388f21dcbc09f8ca34470e4ea5435d57e9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-filepattern
 * [new ref]         d9143c388f21dcbc09f8ca34470e4ea5435d57e9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d9143c3 bump release