Update git submodules

Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 46db4fc8a117f68673efd1d23b224cd1b1880d79
  - Merge "Add repository for OrchestrationTask"
  - Add repository for OrchestrationTask

    Issue-ID: SO-2368

    OrchestrationTask will be used to store the
    slicing options which can be reviewed by the
    maintainer. OrchestrationTask itself is designed
    to be generic and parameters stored inside can
    be customized based on different use cases.

    Change-Id: I42c0639a62bf18f5d0c8bece746cd8e831dd88e8
    Signed-off-by: Harry Huang <huangxiangyu5@huawei.com>