Update git submodules

Update git submodules

* Update docs/submodules/oom/offline-installer.git from branch 'master'
  to 6969393c445e5a86a6e788cff989c4af06ca84ad
  - Merge "Improve kubectl role testability."
  - Improve kubectl role testability.

    Move kubectl related functionality from rancher role to kubectl role
    and change order of execution in playbook to satisfy kubectl role
    dependency to rancher role regarding server value inserted into
    kubeconfig file.

    Introduced defaults and moved technical variables from group_vars
    into role defaults.

    Issue-ID: OOM-1730

    Change-Id: I6339664ba52928566487edcdca8a3b42db86eeed
    Signed-off-by: Samuli Silvius <s.silvius@partner.samsung.com>