$ git clone -n https://gitee.com/src-opencloudos-rpms/postfix.git /var/lib/mock/dist-oc8-build-241858-82903/root/chroot_tmpdir/scmroot/postfix
Cloning into '/var/lib/mock/dist-oc8-build-241858-82903/root/chroot_tmpdir/scmroot/postfix'...
$ git fetch origin 7db0a615f8a5346eae1481928325b1fcf873ec4a:KOJI_FETCH_HEAD
From https://gitee.com/src-opencloudos-rpms/postfix
 * [new ref]         7db0a615f8a5346eae1481928325b1fcf873ec4a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7db0a61 import postfix-3.5.8-8.tl3