Update git submodules

Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Create Gambia Jobs for Yardstick 2/2

    Add Gambia jobs for Yardstick daily.
    Keep fraser jobs until Gambia 7.0.0 is released.

    For fraser-tied PODs, use docker image tag 'ovp-2.0.0'.

    Change-Id: I6dca72807db1caf9adfc5ce5949c50ad70af5361
    Signed-off-by: jenkins-ci <jenkins-opnfv-ci@opnfv.org>
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>
    Signed-off-by: rexlee8776 <limingjiang@huawei.com>
    Signed-off-by: Patrice Buriez <patrice.buriez@intel.com>