Update git submodules

* Update docs/submodules/apex from branch 'master'
  - Merge "Migrates clean to python"
  - Migrates clean to python

    ci/clean.sh will be removed in a future patch after releng is updated to
    use python.

    JIRA: APEX-509
    JIRA: APEX-319

    Change-Id: If890db2fc5a31833ad28ec6f04589e25457bd380
    Signed-off-by: Tim Rozet <trozet@redhat.com>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index 071de3a..7b3a845 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit 071de3a4a11326d5f0c371a2ebeed703f1a40980
+Subproject commit 7b3a8455baa35bdde4d7e078d88f9b17a6df9195