Update git submodules

Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to df5f83eef26b23a5381e134ff50f89b340376596
  - Merge "convert openstack to external tasks"
  - convert openstack to external tasks

    Use external tasks to communicate with openstack adapter
    Will be more resilient to failures
    Refactored all flows to use external tasks not REST calls
    Rollback is now an external task
    Ensured backwards compatibility

    Issue-ID: SO-2767
    Signed-off-by: Benjamin, Max (mb388a) <mb388a@att.com>
    Change-Id: I8afdb89c688d756aed0f25f7d9a7fb898142554d