Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Fix pylint warnings in snaps"
  - Fix pylint warnings in snaps

    Pylint only warns about missing module docstrings now.

    Change-Id: I989ff800cd2628fed80a2d3510ef37ce2876cbd4
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 3547337..9573bce 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 35473374d1eba4814b8344d094e62210ef17d9b1
+Subproject commit 9573bcec95357da8ae07259206fb93919023003d