Update git submodules

* Update docs/submodules/functest from branch 'stable/fraser'
  - Add concurrency parameter to refstack_defcore tests

    In fraser release we observed that refstack tests are executed in parallel
    and that might causes problems in CI because without concurrency
    parameter it will try to use as many cpus as possible and that might
    lead to race condition issues.

    This patch is created for backporting purposes to fraser branch
    where the problem occurs.

    JIRA: DOVETAIL-662

    Change-Id: I6cf0ad3a32e88f04abd00d69523aa8ac47c39470
    Signed-off-by: Dimitrios Markou <mardim@intracom-telecom.com>
    (cherry picked from commit d5c3692d211cb3e82708eaf2595ba3f26fafc6a6)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 30fc5f1..3545d54 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 30fc5f1f2d1ef94d94a96b54739f82fac8b1aecd
+Subproject commit 3545d54a9ac4713d44168c800b171b8186fb4371