Update git submodules

* Update docs/submodules/yardstick from branch 'stable/danube'
  - Merge "yardstick offline support" into stable/danube
  - yardstick offline support

    JIRA: YARDSTICK-597

    Currently yardstick can not run offline.
    The reason is yardstick will pull the latest code when run in CI.
    Actually we need not pull the latest code because the code in yardstick
    is already the latest code.
    So I remove them.

    Change-Id: Ief87c529625ccaa26e758a2206318b3797bbfd74
    Signed-off-by: chenjiankun <chenjiankun1@huawei.com>
    (cherry picked from commit 52634e40e5668e2d8c031781d1b15b482b0511f4)

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index c97a190..a900273 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit c97a1907549f841cc5b2d2efeacea7c703b0de3f
+Subproject commit a900273be090491ce71f9e78ac456c49093e3f71