Update git submodules

Update git submodules

* Update docs/submodules/multicloud/k8s.git from branch 'master'
  to 7cb9c0b9e9ee87f962c1a678471f24b14b02ec85
  - Added the new plugin_collection_v2 script.

    The script calls the major creation APIs in v2 starting from project api, composite app, composite profile, generic placement intent & deployment intent. This should be used every time we need to test the  Instantiation code.
    Also added the helm charts for composite app consisting of collectd and
    prometheus.

    Issue-ID: MULTICLOUD-1035
    Signed-off-by: Rajamohan Raj <rajamohan.raj@intel.com>
    Change-Id: I95237c234cca674dd54f4ef7527083b5cf3e0a55