Update git submodules

Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[fuel] verify: Multiarch, docker build step"
  - [fuel] verify: Multiarch, docker build step

    Rework Fuel verify jobs:
    - split 'fuel-verify' into per-arch jobs (amd64 and arm64):
      * for now, arm64 jobs are non-voting;
    - add 'docker-build' phase job:
      * the docker build job will run on the same virtual POD jump host
        as the deploy, to bypass the need of pushing to a (public)
        Docker hub registry - this might be refactored later to resemble
        the old Fuel ISO build workflow where the artifacts built during
        verify are the ones actually promoted - with the current method
        the final build & tag (ran on OPNCI CI build servers) might yield
        different results due to different docker build cache states;
      * the locally built container image is tagged with the 'verify'
        designator and not pushed to a public registry, only consumed
        during verify's job 'deploy-virtual' phase;

    JIRA: ARMBAND-401
    JIRA: FUEL-383

    Change-Id: I9b0d8079e759cdc895260219a8a4989411c995ff
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>