Update git submodules

* Update docs/submodules/apex from branch 'master'
  - Merge "Removing sdn_l3 and _l2 scenario features"
  - Removing sdn_l3 and _l2 scenario features

    JIRA: APEX-429

    Change-Id: Ifb28bb27f8e58ac5b180454719dfb329c3edf000
    Signed-off-by: Dan Radez <dradez@redhat.com>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index b411839..55fdc0e 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit b411839804e6fca023ef7a695bbb616ea80fd6f3
+Subproject commit 55fdc0e0418ea23a4ca208ae3285e03e04a612e5