Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Adding support to pull docker images behind proxy"
  - Adding support to pull docker images behind proxy

    This patch creates a http_proxy.conf in docker service,
    to enable docker commands behind the proxy

    Change-Id: Iac38a086026c11e89e534728467dc7da0e01ba59
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 92098cd..69d5e6b 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 92098cdeb1d0d21ceea33f4f234d7b383ab46f14
+Subproject commit 69d5e6b288d16b5f9cab57859670d651eccd5e26