$ git clone -n https://src.fedoraproject.org/rpms/fedora-iot-config.git /var/lib/mock/f40-build-1996257-43997/root/chroot_tmpdir/scmroot/fedora-iot-config
Cloning into '/var/lib/mock/f40-build-1996257-43997/root/chroot_tmpdir/scmroot/fedora-iot-config'...
$ git fetch origin 0a664dfaa3135f4db66976ee85128124aa2c18e6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/fedora-iot-config
 * [new ref]         0a664dfaa3135f4db66976ee85128124aa2c18e6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0a664df Bump spec for new release