Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "lib.sh: Reduce useless wget dot reporting"
  - lib.sh: Reduce useless wget dot reporting

    Downloading the base image (usually a few hundred MB) outputs a lot
    of useless dots to show progress. Switch to 1M per dot (from 1K).

    Change-Id: I8c525cad0b46e8ba3a7f6da4dd7f8277a49df91f
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 2bd6a0e..8bb7aa8 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 2bd6a0ed390285ec8f17cc8c71a9147485ca860b
+Subproject commit 8bb7aa853357117649441946ed1553d907b37871