Update git submodules

* Update docs/submodules/yardstick from branch 'stable/fraser'
  - Merge "Cleanup BaseMonitor unit tests" into stable/fraser
  - Cleanup BaseMonitor unit tests

    Stop multiprocessing queues to avoid BrokenPipe exception.
    Assert correctly the raise of exceptions.

    JIRA: YARDSTICK-1229

    Change-Id: I1a1c92c49a439283a35c9a69b59d6866f35ec09a
    Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>
    (cherry picked from commit 94d56c9f7cd99baea08629eaf3e580d020494383)

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 5d3a4a8..d5f86f8 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 5d3a4a8c10fdde34e16381cb8f16450837d33af3
+Subproject commit d5f86f8af56c19e0ce127522b72fbe3501e18b1d