Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [virtual] Switch compute nodes to uca repo

    Test of snaps_health_check gets console output of instance, which is
    empty (https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1667033),
    therefore take affected packages of computes from UCA repo.

    Change-Id: I4e13a40dd47caf305efd9f393b3c3cf5a17ef312
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index ec3604c..c76d5e9 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit ec3604c1a30981ad7e9d3a9ea82f61391c1266cf
+Subproject commit c76d5e92d9e6cdfc614be4a1ed7b9e630c711008