Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Cleanup GetDataDbClientTestCase unit tests"
  - Cleanup GetDataDbClientTestCase unit tests

    Removed unneeded output.

    JIRA: YARDSTICK-1268

    Change-Id: I2e9130e863ba915feeb52f54fc901898b1c8f792
    Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 494810c..9b18991 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 494810c4d113088069d6d2746bb40f988c583ef3
+Subproject commit 9b1899199dab5094374b8beda850af92e6f55491