Update git submodules

* Update docs/submodules/functest from branch 'stable/fraser'
  - Read thirdparty-requirements.txt if py3

    It fixes the current build issues due to unsynced doctor [1].

    [1] https://build.opnfv.org/ci/job/functest-features-docker-build-arm64-master/455/console

    Change-Id: Iad8b667e2615dcd976cd8120e4204665134922b7
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit 01509097c7447ee70d61f7e97d7947b127425eac)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index c3d95cf..5400c81 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit c3d95cf0aa98f8a87685ec7677c493707499171a
+Subproject commit 5400c8133810b7538f26b83b30e9ab5be29f79c6