$ git clone -n https://src.fedoraproject.org/rpms/cyrus-imapd.git /var/lib/mock/f40-build-792298-138328/root/chroot_tmpdir/scmroot/cyrus-imapd
Cloning into '/var/lib/mock/f40-build-792298-138328/root/chroot_tmpdir/scmroot/cyrus-imapd'...
$ git fetch origin f7ad189e5eac3807fef9317bc775eaee93e4ffd6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cyrus-imapd
 * [new ref]         f7ad189e5eac3807fef9317bc775eaee93e4ffd6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f7ad189 Do not create mail group to prevent dependency loop (rhbz#2266335)