Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - docs: diagrams: Add PXE/admin on cfg01

    Refresh diagrams to reflect that the internal network is not used
    anymore on jumpserver after PXE/admin was hooked to cfg01.

    Change-Id: I4c162d59824e182bc76c0a395742050544e95291
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 90c0b36..bb3a642 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 90c0b369c01a2185fe86651f8ad9e0a172d6941d
+Subproject commit bb3a642e783b59ae2decb3b73d91f5bfca3afaef