$ git clone -n https://gitee.com/uestc-cheng/libxml2.git /var/lib/mock/dist-an8.8-build-299376-65890/root/chroot_tmpdir/scmroot/libxml2
Cloning into '/var/lib/mock/dist-an8.8-build-299376-65890/root/chroot_tmpdir/scmroot/libxml2'...
$ git fetch origin 3dcd084d7cff905fb26c9919a1f69181aaaf3030:KOJI_FETCH_HEAD
From https://gitee.com/uestc-cheng/libxml2
 * [new ref]         3dcd084d7cff905fb26c9919a1f69181aaaf3030 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3dcd084 update libxml2.spec.