$ git clone -n https://gitee.com/uestc-cheng/libxml2.git /var/lib/mock/dist-an8.8-build-299125-65888/root/chroot_tmpdir/scmroot/libxml2
Cloning into '/var/lib/mock/dist-an8.8-build-299125-65888/root/chroot_tmpdir/scmroot/libxml2'...
$ git fetch origin de3d9e11e1fd7afa602eeb4226c0413d6481f23a:KOJI_FETCH_HEAD
From https://gitee.com/uestc-cheng/libxml2
 * [new ref]         de3d9e11e1fd7afa602eeb4226c0413d6481f23a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at de3d9e1 update libxml2.spec.