Update git submodules

* Update docs/submodules/yardstick from branch 'stable/gambia'
  - Merge "Add OvS 2.8.1 support into SA context" into stable/gambia
  - Add OvS 2.8.1 support into SA context

    JIRA: YARDSTICK-1462

    Change-Id: I001a173fc728be6e88f5ae6d38c64b740e536ff2
    Signed-off-by: Mytnyk, Volodymyr <volodymyrx.mytnyk@intel.com>
    (cherry picked from commit ad63af7f42d07cffde73c32727f170973ce5ba46)

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 02aa6ce..e17ba5d 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 02aa6ce47db11f92bc343307fb7fe67dcc86f773
+Subproject commit e17ba5d730878ae2a92cc9130e47630cc6745d91