Update git submodules

Update git submodules

* Update docs/submodules/multicloud/k8s.git from branch 'master'
  to 838ddaa50041ac4c33adeb2c8a33340fdfe2c952
  - Merge "NewRouter supports custom backend clients"
  - NewRouter supports custom backend clients

    NewRouter needs to support custom clients
    This is needed where the backend clients are mocked
    and we need url path parameters to be available in our
    unit tests.
    Using the same router code allows us to do this.

    Issue-ID: MULTICLOUD-547
    Change-Id: Id51b6f0a9afe4965efaf2611fc642bccb9ac1d39
    Signed-off-by: Kiran Kamineni <kiran.k.kamineni@intel.com>