Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to cfcb2684902aa01d60d1d7367da58813ac2151c0
  - Merge "Update Working with SO Docker Documentation"
  - Update Working with SO Docker Documentation

    patch description: Update Working with SO Docker
    documentation for casablanca release.

    Change-Id: If7a4601e83e0ca83f99a9f74e1f282abc3854bdd
    Issue-ID: SO-1505
    Signed-off-by: mohamed waly <mohamed.waly@orange.com>

diff --git a/docs/submodules/so.git b/docs/submodules/so.git
index 55150d5..cfcb268 160000 (submodule)
--- a/docs/submodules/so.git
+++ b/docs/submodules/so.git
@@ -1 +1 @@
-Subproject commit 55150d59330da44b59ae7a643ee5938761cf8b70
+Subproject commit cfcb2684902aa01d60d1d7367da58813ac2151c0