Update git submodules

Update git submodules

* Update docs/submodules/portal.git from branch 'master'
  to 3992004ee5f2b0b1635e2aef19c375db87079b52
  - Reduce image size of containers

    CIA project goal is to reduce image size of container and make the
    container multi architecture.

    Portal images are already multi architecure ready and portal-wms and
    portal-db are also done in an efficient way.

    Portal-app and portal-sdk although can be shrinked, using multi stage
    docker builds.

    This commit allow a noticeable shrink for both of them:

    from 708Mb to 298Mb for portal-app and from 388Mb to 257Mb for
    portal-sdk.

    Change-Id: Id5cca8b78d0d9ee1724259dab40b7ccff910c628
    Issue-ID: INT-939
    Issue-ID: INT-922
    Issue-ID: INT-881
    Issue-ID: INT-925
    Issue-ID: INT-936
    Signed-off-by: Sylvain Desbureaux <sylvain.desbureaux@orange.com>