Update git submodules

* Update docs/submodules/apex from branch 'stable/fraser'
  - Fixes OVN scenario

    The OVN scenario would not deploy due to failures in trying to upgrades
    to OVS 2.8 from OVS 2.7

    JIRA: APEX-594.

    Change-Id: Id84e488da8d2335f2240930c68119d0e2f6faf9c
    Signed-off-by: Tim Rozet <trozet@redhat.com>
    (cherry picked from commit ee70c386a8560303693082f449543ad36f0f2f9c)

diff --git a/docs/submodules/apex b/docs/submodules/apex
index e5caea3..340a247 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit e5caea32820466d5870f11ba72255b8f77591a62
+Subproject commit 340a2478d1e2c89511e3245e30ccefa216f5473c