$ git clone -n https://gitee.com/mgb01105731/gstreamer1-plugins-base_4.git /var/lib/mock/dist-an23-build-441397-73164/root/chroot_tmpdir/scmroot/gstreamer1-plugins-base_4
Cloning into '/var/lib/mock/dist-an23-build-441397-73164/root/chroot_tmpdir/scmroot/gstreamer1-plugins-base_4'...
$ git fetch origin b9d40196f1d82b385315e4388de7051d104417f2:KOJI_FETCH_HEAD
From https://gitee.com/mgb01105731/gstreamer1-plugins-base_4
 * [new ref]         b9d40196f1d82b385315e4388de7051d104417f2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b9d4019 redbuild for libtheora