Update git submodules

* Update docs/submodules/bottlenecks from branch 'master'
  - Add life-cycle throughputs testcase

    JIRA: BOTTLENECK-186

    Add skeleton of this test case:
    1. Quotas modification
    2. Call Yardstick to run test

    Change-Id: I02726bbfb2104151e5ef3c52a214775d30f9e743
    Signed-off-by: Gabriel Yu <Gabriel.yuyang@huawei.com>

diff --git a/docs/submodules/bottlenecks b/docs/submodules/bottlenecks
index 7b61cfd..d6f6b68 160000 (submodule)
--- a/docs/submodules/bottlenecks
+++ b/docs/submodules/bottlenecks
@@ -1 +1 @@
-Subproject commit 7b61cfd2e0c7bed6004f82d11b4cdc37a2e12cad
+Subproject commit d6f6b682701c16ebf21e0da99fbc8883147a8ffe