Update git submodules

* Update docs/submodules/oom/offline-installer.git from branch 'master'
  to d8c6d9acfd8b74dc3f3187d069b393405e5c1b18
  - Archive helm_charts with command module

    Due to bug in ansible archive module empty files are not added into tar file.
    Hence kibana-onborading.json missing in helm_charts on infra node.
    Changing archive module into command module to tar helm_charts.

    Issue-ID: OOM-2231
    Signed-off-by: Ondřej Šmalec <o.smalec@partner.samsung.com>
    Change-Id: I5527bd0f52976a93ac2861d9de010fbb79eb97fd

diff --git a/docs/submodules/oom/offline-installer.git b/docs/submodules/oom/offline-installer.git
index 610ddff..d8c6d9a 160000 (submodule)
--- a/docs/submodules/oom/offline-installer.git
+++ b/docs/submodules/oom/offline-installer.git
@@ -1 +1 @@
-Subproject commit 610ddff2d54cece28af56cc7bbf01ed524ecce9c
+Subproject commit d8c6d9acfd8b74dc3f3187d069b393405e5c1b18