$ git clone -n https://src.fedoraproject.org/rpms/buildbot.git /var/lib/mock/f40-build-2692449-68209/root/chroot_tmpdir/scmroot/buildbot
Cloning into '/var/lib/mock/f40-build-2692449-68209/root/chroot_tmpdir/scmroot/buildbot'...
$ git fetch origin d9a72b4ccb4824426f51fdbaac1024ee01e63449:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/buildbot
 * [new ref]         d9a72b4ccb4824426f51fdbaac1024ee01e63449 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d9a72b4 PAtch