Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "runners: add timeout to queue put"
  - runners: add timeout to queue put

    we don't want to block the test waiting to put KPIs
    Add moderate timeout.  In case we do timeout, it
    doesn't matter if we drop intermitten KPIs

    Change-Id: I049c785355993e6b286748a5c897d54dd2923dc9
    Signed-off-by: Ross Brattain <ross.b.brattain@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index cec4342..e8cf6a7 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit cec4342dee5c13260b680f6dddbc33ae5bf0c127
+Subproject commit e8cf6a76c346806b53fa0c802374327ddc4956d1