Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [docker] Add MCP_DOCKER_TAG env var

    Allow skipping docker pull for verify jobs by setting the new env
    var to 'verify'.

    JIRA: FUEL-383

    Change-Id: If8e2f66b5ccdac5c3911eeabfc2ba9c0eba61093
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 36169a1..546d392 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 36169a124d25dd77b7525cd5223525db4342c208
+Subproject commit 546d3927a8ecd822b319a8eac1f98983df63eb3a