Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'stable/danube'
  - Remove vping_ssh from bgpvpn and gluon scenario

    Cause of the bug:
    https://bugs.opendaylight.org/show_bug.cgi?id=5586
    Floating ip is not working at the moment for us.

    We don't want to remove the vping_ssh test from
    fuel. the scenarios are called different in fuel and
    in apex. odl-bgpvpn in apex. odl_l2-bgpvpn in fuel.

    Change-Id: Iaa2e6cea8a4fdb8635f018427aaf30634fd8d2d5
    Signed-off-by: Nikolas Hermanns <nikolas.hermanns@ericsson.com>
    (cherry picked from commit 5af67bcca589c275b73fe5e4bca9bea5871948aa)