$ git clone -n https://src.fedoraproject.org/rpms/dovecot.git /var/lib/mock/f40-build-2434294-60739/root/chroot_tmpdir/scmroot/dovecot
Cloning into '/var/lib/mock/f40-build-2434294-60739/root/chroot_tmpdir/scmroot/dovecot'...
$ git fetch origin cd7e39531b15a322fbb0e92cd854d631b6881d35:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dovecot
 * [new ref]         cd7e39531b15a322fbb0e92cd854d631b6881d35 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cd7e395 allow dtpath for plugins