Update git submodules

* Update docs/submodules/sdnvpn from branch 'stable/danube'
  - Merge "remove testing docs" into stable/danube
  - remove testing docs

    Change-Id: I76af05c6b3dbd945d4c027ea3dc58ae1e5357418
    Signed-off-by: Nikolas Hermanns <nikolas.hermanns@ericsson.com>
    (cherry picked from commit a8ac0683dc4accfc4d300de20071989c0d1ffb63)

diff --git a/docs/submodules/sdnvpn b/docs/submodules/sdnvpn
index a0fe19b..85eb1a2 160000 (submodule)
--- a/docs/submodules/sdnvpn
+++ b/docs/submodules/sdnvpn
@@ -1 +1 @@
-Subproject commit a0fe19bb8f627a3e6af105213edbf6a71a0e73ea
+Subproject commit 85eb1a22ae325283a1e23677af4d784e66be694d