Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "Enable barbican itegration on compute nodes"
  - Enable barbican itegration on compute nodes

    Configure barbican for cinder-volumes and nova-compute
    to use encrypted volumes
    Disable default glance image signature verification with
    barbican enabled

    JIRA: FUNCTEST-981

    Change-Id: I35660234526780a2277e459f3fa21a67d96ce7d7
    Signed-off-by: Delia Popescu <delia.popescu@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index b466cb8..143bf77 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit b466cb8270ebf9515d6acbad4d4dcfe28af47dd6
+Subproject commit 143bf770cf104daaf8d457a3de294d6acb33f9cf