Update git submodules

Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Pin functest-healthcheck docker image to known sha

    Functest changes have significant impact which blocks everything in XCI so this
    change pins the image to a known sha to get the original set of healthcheck
    testcases until the impacts are analysed and concerns are raised to Functest
    and the wider OPNFV Community and addressed based on community consensus.

    Pinned version of functest-healthcheck contains the test cases below.
    - connection_check
    - api_check
    - snaps_health_check

    deploy-scenario:os-nosdn-nofeature
    installer-type:osa

    Change-Id: Ic9222af8c27e58491b7b60a7504df9d792b5e753
    Signed-off-by: Fatih Degirmenci <fdegir@gmail.com>