Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Fix the yamllint errors in functest/ci"
  - Fix the yamllint errors in functest/ci

    And also, remove the params "tempest_use_custom_images" and
    "unique_names" of vping, rally and tempest.

    Change-Id: Ic4243ef2f5e965910e5befa87db8d585cad34fa2
    Signed-off-by: Linda Wang <wangwulin@huawei.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 2800b22..04886b1 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 2800b22d762e938727ec4b466178eca4de05006d
+Subproject commit 04886b12a4f5c3f18c71f0ca78fdbcf8a545f5f6