Update git submodules

Update git submodules

* Update docs/submodules/oom/offline-installer.git from branch 'master'
  to 1bfd41937210685fb9a9ac318d124f16acdbe274
  - Merge "Simplify Centos Dockerfile for Molecule"
  - Simplify Centos Dockerfile for Molecule

    Base the Centos image for molecule on official
    CentOS systemd docker container.

    Align the tagging policy with Centos images
    on docker hub.

    Change-Id: Ia2743ab78faed858dc5a7f3611cffb779b23d463
    Issue-ID: OOM-1774
    Signed-off-by:  Bartek Grzybowski <b.grzybowski@partner.samsung.com>