Update git submodules

* Update docs/submodules/apex from branch 'stable/fraser'
  - Default ctlplane to native VLAN

    We were not setting any vlan type value for the admin network.  This
    caused an issue when deploying and trying to use a single collapsed
    network (no net isolation).  The issue occurred when trying to create an
    external neutron network.  We happen to check if the phys type is flat
    or vlan using this attribute to decide what kind of phys type to use for
    the neutron network.

    JIRA: APEX-606

    Change-Id: I4e24dd5e8b99cef920b8203b820a77d0021631cc
    Signed-off-by: Tim Rozet <trozet@redhat.com>
    (cherry picked from commit 42a9303a21a46f9e9b1997ab4c0beceb6b0bf438)

diff --git a/docs/submodules/apex b/docs/submodules/apex
index fd7f328..073cf28 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit fd7f3285fa0d872f3eb23ded248e45bf720ebda7
+Subproject commit 073cf28764cd3700916f57e43741ff20e4af57e5