Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'stable/euphrates'
  - Define thirdparty-requirements.txt for functest-parser

    As Parser python packages has been renamed, they can be defined in
    upper-constraints.txt. No conflict can occur between them and the
    official OpenStack packages.

    The Parser testcase still requires a dedicated container to avoid
    conflicts in namespaces.

    Conflicts:
        docker/parser/Dockerfile
        upper-constraints.txt

    Change-Id: Ic8d18140f26e72d1e3d04b73d301d3fd870b171a
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit f77c464a9bf40b36586843ae59e6764216477c4b)