Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 641d9e6b68a964dc69dbec7c63f82e73b61433e2
  - Merge "Fixed possible NPE in ResourceRequestBuilder"
  - Fixed possible NPE in ResourceRequestBuilder

    According to Sonar current implementation could cause
    NullPointerException.
    Added JUnit test.

    Change-Id: I840c018bed346d85e2042c7308bdd27197f50b46
    Issue-ID: SO-1498
    Signed-off-by: Robert Bogacki <r.bogacki@samsung.com>

diff --git a/docs/submodules/so.git b/docs/submodules/so.git
index 5b575de..641d9e6 160000 (submodule)
--- a/docs/submodules/so.git
+++ b/docs/submodules/so.git
@@ -1 +1 @@
-Subproject commit 5b575deb4de10d9520ac7a117702e526e8872c95
+Subproject commit 641d9e6b68a964dc69dbec7c63f82e73b61433e2