Update git submodules

* Update docs/submodules/apex from branch 'stable/danube'
  - Build and deployment fixes for danube

    - Remove puppet-neutron-add-odl-settings.patch file, this patch is now
      included in overcloud images.
    - Add retry for pacemaker::stonith resource to avoid resource creation
      failure during deployment

    opnfv-puppet-tripleo-pr: 27

    Change-Id: I8440e7ddc290d04135e8cd82b2136cc245dc980a
    Signed-off-by: Feng Pan <fpan@redhat.com>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index 67c9014..983c23e 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit 67c901485aa5a46d05833edc534f202463bf9f9e
+Subproject commit 983c23e49dd1312c7cf66d528261441be458b29e