Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [mcp] Copy ssh key to tmp dir

    Copy ssh key to tmp dir to be able to retrieve
    OS credentials by releng/utils/fetch_os_creds.sh

    Also adds 'set -x' to ci/deploy.sh

    Change-Id: I056c626288862f84f47c947461894730ce0483ac
    Signed-off-by: Andrii Ostapenko <aostapenko@mirantis.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index d433573..4f68016 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit d433573b98d288feaff518dd3ac9a5b19e35f1e6
+Subproject commit 4f68016daa6b8bff677b9915b411fda388f5505d