Update git submodules

Update git submodules

* Update docs/submodules/clover from branch 'master'
  - Merge "Fix Nginx lb in k8s/istio"
  - Fix Nginx lb in k8s/istio

    - Provide workaround to make nginx lb work properly
    - nginx_client sample can modify default load balancing
    from three to two servers at runtime
    - Ensure port 9180 is used for default deploy for lb and
    servers
    - Modify render_yaml to specify deploy_name so that
    clover-server1, 2, 3 can be used for default lb config
    - Ensure proxy template is aligned to lb to allow the
    source IP from originating host to be propagated to final
    destination

    - Fix default nginx proxy server_name to 'proxy-access-control'
    and change default proxy destination to 'http-lb'
    - Split lb service_type to 'lbv1' and 'lbv2' to provide an example
    of how to modify the run-time configuration of the load balancer
    after deployment - modify http-lb-v2 to use clover-server4/5 instead
    of the defualt clover-server1/2/3 - modify http-lb-v1 to use
    clover-server1/2 instead of 1/2/3
    - Aligned pod IP retrival method with nginx_client.py

    Change-Id: I73fa60a69c93ae1e82a477ef6283c00f67a21360
    Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>