Update git submodules

Update git submodules

* Update docs/submodules/clover from branch 'stable/gambia'
  - Merge "Initial commit of Jmeter validation config guide" into stable/gambia
  - Initial commit of Jmeter validation config guide

    - Provides brief overview and usage instructions including:
      - delete/deploy in k8s using cloverctl CLI and source
      - Generate the test plan on the master
      - Start tests on master or with slaves
      - Retrieve results using cloverctl and interpret
    - Embedded images forthcoming

    Change-Id: Ibbfa21f5d73c76c16ffac115ad0164c5cf210236
    Signed-off-by: earrage <eddie.arrage@huawei.com>