Update git submodules

Update git submodules

* Update docs/submodules/clover from branch 'master'
  - Merge "Added initial nginx services"
  - Added initial nginx services

    - Proxy allows ingress traffic to be sent to another element in
    service mesh
    - Mirroring is also in the default configuration
    - Default configuration is to proxy to a clover-server and mirror
    to snort-ids
    - A location_path (URI in HTTP requests) can be reconfigured to
    restrict proxing; default to '/'
    - A proxy_path can be reconfigured to specify an alternate destination
    - A mirror path can be reconfigured to specify where traffic
    will be spanned
    - The default server_port (listen port) for the proxy is 9180 but can be
    reconfigured
    - The default server_name is http-proxy but can be reconfigured
    - Reconfiguration is done over GRPC with jinja2 template for nginx
    - Currently snort ids sends alerts to proxy with stub code in GRPC

    - Refactored the code to have a nginx base with subservices
    - Proxy, Load Balancer (lb), and Server can share code - mainly GRPC
    server
    - Nginx subservices have separate docker builds

    - Improved build scripts for CI
    - Render yaml manifests dynamically
    - Improve nginx_client for runtime modifications (but not really
    useful yet)

    Change-Id: Icbff6890021bcc8a8da4690c9261205d6e1ca43a
    Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>