Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Fix pylint errors in several utils modules"
  - Fix pylint errors in several utils modules

    All utils which are moving to xtesting are now fixed.
    It remains OpenStack and Functest utils (+ the related unit tests)
    which doesn't move to the new package.

    Change-Id: If13c627c8444c62d5c6bf9c8057d6413aa0e56c7
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 18c016a..630a316 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 18c016a2eaf65fec880a04bcc354f52e9cdb4417
+Subproject commit 630a31629bffd6d881faf2e3ea3a849b4143c103