Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Start nginx and uwsgi servicies only in not container mode"
  - Start nginx and uwsgi servicies only in not container mode

    No need to execute nginx and uwsgi when running in container mode.

    JIRA: YARDSTICK-1179

    Change-Id: I253f3adab388a14886b70e6589936f6eb27ac4c0
    Signed-off-by: Stepan Andrushko <stepanx.andrushko@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index ebeb81e..2bd4d48 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit ebeb81ea222770e2f5330b680a8a13f587e023e8
+Subproject commit 2bd4d480868048e84ed81662b2d34e03f25502a4