Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Harden Rally generate report

    It converts html_file to str and raises all possible exceptions.
    It sometimes fails when locally generating reports.

    Change-Id: Idf6a12aaac4561800cd5e364f8bcc495aabbee1d
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 6939526..4d3627e 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 6939526b9802539a62f71ca7759f7bd49c16aef4
+Subproject commit 4d3627e56d333e313b67bbf1e7880b11883b5652