Update git submodules

* Update docs/submodules/functest from branch 'stable/euphrates'
  - Bump os-faults version to 0.1.15

    For Rally stable/0.9, os-faults version has been constrained
    as ">=0.1.15,<0.2.0" [1].

    [1]: https://github.com/openstack/rally/blob/stable/0.9/requirements.txt

    JIRA: PROMISE-88

    Change-Id: Ifeb36e1debf23edf6d914e9db60be11d4ca557cd
    Signed-off-by: Linda Wang <wangwulin@huawei.com>
    (cherry picked from commit 945b4412574d87a1ed700e59fa8ffeea92dc9e0d)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index ca3d68f..249864c 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit ca3d68ff33a8c9668e71ecc847a1391124d6a4ab
+Subproject commit 249864cfb9c4b08e95a7a616c09f2c36b5a56c5d