Update git submodules

Update git submodules

* Update docs/submodules/oom/offline-installer.git from branch 'master'
  to 8013a2420fff9059cc67ccae22a1abeea4e26542
  - Merge "Adding Ubuntu support in Ansible - kubectl role"
  - Adding Ubuntu support in Ansible - kubectl role

    Extending ansible playbooks of ubuntu support.
    Creating new test with Ubuntu image for Molecule in kubectl role.

    Issue-ID: OOM-1671
    Signed-off-by: Jan Benedikt <j.benedikt@partner.samsung.com>
    Change-Id: I707ff9f609ece2b227dd84f32fdf519019f76e80