Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[cfg01] apt.conf.d: Dpkg::Use-Pty: 0"
  - [cfg01] apt.conf.d: Dpkg::Use-Pty: 0

    This will silence all 'Reading database ...' noise during Salt formula
    installation.

    Change-Id: I734d727194e276443db1e1581f40ec494562196e
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 8bb7aa8..c5e54b7 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 8bb7aa853357117649441946ed1553d907b37871
+Subproject commit c5e54b7cd6e45657fdde0e456fdebff23489bb5a