Update git submodules

* Update docs/submodules/apex from branch 'master'
  - Merge "Adds missing packages for undercloud"
  - Adds missing packages for undercloud

    JIRA: APEX-511

    Change-Id: If8ed2b5409e450c39f4fffd5a0b3cb96560c5d26
    Signed-off-by: Tim Rozet <trozet@redhat.com>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index 2ecb25b..57b9c05 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit 2ecb25bea8dbb8abc7bd4f90f07101b40e70363b
+Subproject commit 57b9c05dd1881b7b4ddd2f97fdbd80047d6eb3ca