Update git submodules

Update git submodules

* Update docs/submodules/multicloud/k8s.git from branch 'master'
  to def02dfebada38bde91dc98db85eff3d8923a923
  - Add apps under composite app API

    Implemented create, get and delete
    handlers for the apps under composite
    app.

    Added unit tests

    Added remove function to mockdb

    Handled multipart POST request to
    upload file along with app data.

    Issue-ID: MULTICLOUD-998
    Signed-off-by: Srivahni Chivukula <srivahni.chivukula@intel.com>
    Change-Id: I25c1faba1212c0cc881c2cd599e8e66a7b93033e