Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Fix the doc of snaps test

    snaps_health_check does not allocate a floating ip to the vm,
    but a fixed ip instead.

    Change-Id: Ia43885993135dec56aba08b0e157ac2c9f715e06
    Signed-off-by: Linda Wang <wangwulin@huawei.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 3e4359e..8e1f8d7 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 3e4359ed4b18f740ef9a99e2bf8415c005728f98
+Subproject commit 8e1f8d7b761102c17d7b9233b24906d3ac33085c