Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Bugfix: supoort insecure mode in checking openstack environment"
  - Bugfix: supoort insecure mode in checking openstack environment

    Change-Id: I18346aa177689bc995eb7d4883f4a66383e827ba
    Signed-off-by: JingLu5 <lvjing5@huawei.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index e665345..e2601af 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit e665345b9681ceca6b950ecbbd4e88dd1be5acda
+Subproject commit e2601afe686e29e3c6109637e43208b5c6132e74