$ git clone -n https://src.fedoraproject.org/rpms/ghc-yesod-persistent.git /var/lib/mock/f41-build-840800-160954/root/chroot_tmpdir/scmroot/ghc-yesod-persistent
Cloning into '/var/lib/mock/f41-build-840800-160954/root/chroot_tmpdir/scmroot/ghc-yesod-persistent'...
$ git fetch origin b276904c96dc1b140b112421819fe36a1645d959:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-yesod-persistent
 * [new ref]         b276904c96dc1b140b112421819fe36a1645d959 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b276904 bump release