Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 23c402203aa8bba6fd2f93e9d95871a40f22b4ed
  - Merge "Changed the text xml client to always set the"
  - Changed the text xml client to always set the

    Changed the text xml client to always set the accept type to text xml.
    Forgot to assign the accept type in rest client

    Issue-ID: SO-2838
    Signed-off-by: Benjamin, Max (mb388a) <mb388a@att.com>
    Change-Id: Ia86e53327c6e126fcee6a15b5cd3e5f5c4ec9390