Update git submodules

* Update docs/submodules/apex from branch 'stable/euphrates'
  - Fixes apex ISO missing python2-jmespath

    Installing ansible depends on python2-jmespath which was missing in the
    ISO.  This patch adds it to the ISO build.

    Change-Id: I18e76168273537a1682fb7187e5a2c72aacab296
    Signed-off-by: Tim Rozet <trozet@redhat.com>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index f9cdd78..1a20188 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit f9cdd787b22a286daebecb14532b437939687c5e
+Subproject commit 1a20188ff7804487ddc3ac457f12cf765ef186ce