Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Update unit test related to vyos_vrouter"
  - Update unit test related to vyos_vrouter

    Utilvnf is now mocked to stop triggering the git clone of an
    external repo and creating dirs.
    Else we may get errors when testing offline.

    Co-Authored-By: Cédric Ollivier <cedric.ollivier@orange.com>
    Change-Id: Ia7e86593ecca9b9add747ef89b1d5e8d6bdb2d7c
    Signed-off-by: Morgan Richomme <morgan.richomme@orange.com>
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>