Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Add "ports" parameters in Kubernetes context

    This new parameter, "ports", will allow the user to
    automatically to add port variables in a pod definition:
    context:
      type: Kubernetes
        servers:
            host:
                image: ...
                commands: ...
                ports:
                    - containerPort: <port value>    # Mandatory
                      hostIP: <host IP>              # Optional
                      hostPort: <host port>          # Optional
                      name: <port name>              # Optional
                      protocol: <protocol name>      # Optional

    The port type and the definition must be one of the supported ones
    in Kubernetes [1].

    Container port definition, V1 API, Kubernetes Python library v6.0.0 [2]

    [1] https://kubernetes.io/docs/concepts/services-networking/connect-applications-service/
    [2] https://github.com/kubernetes-client/python/blob/6.0.0/kubernetes/client/models/v1_container_port.py

    JIRA: YARDSTICK-1183

    Change-Id: I3673dbeec8d380cb2f8b1dacf6c25c7cdbc37e28
    Signed-off-by: John O Loughlin <john.oloughlin@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 028e92b..ff3cd7a 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 028e92b1b2dcbaffd4a80061cc3d387877b59d62
+Subproject commit ff3cd7a245840606b09322c7705f8a64cf1868f2