Update git submodules

Update git submodules

* Update docs/submodules/oom/offline-installer.git from branch 'master'
  to 7e5ddf0b3e0f23bf499b3311340253485d06fc33
  - Merge "Add prepare-docker-dind role"
  - Add prepare-docker-dind role

    This change adds the prepare-docker-dind role intended to
    be used in tests to install docker on test containers.
    Contrary to the prepare-docker role it arranges for docker daemon to be launched inside
    of the test containers instead of using/polluting a test host.
    It is a prerequisite to the rke role molecule tests.

    Change-Id: I6be270758b01f7e9c4fa09aebcc32930c0977ea3
    Issue-ID: OOM-1778
    Signed-off-by: Michal Zegan <m.zegan@samsung.com>