Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Update neutron delete_neutron_net function."
  - Update neutron delete_neutron_net function.

    Update the changes done in patch [1].

    JIRA: YARDSTICK-890

    [1] https://gerrit.opnfv.org/gerrit/#/c/52361/

    Change-Id: Iccbf16d0a2e72919d5092366241ff41686f01a58
    Signed-off-by: Shobhi Jain <shobhi.jain@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 156df0c..810410c 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 156df0ca22164a7cb7b474230851bc04f688e49f
+Subproject commit 810410c8a30ffc5f4ef48923721f816c9a6e0871