Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [baremetal] Add upstream (lab) proxy support

    If upstream proxy is defined in IDF, propagate it to pillar data:
    - linux:system:proxy:keyserver:http(s) for cfg01, mas01;
    - maas:region:upstream_proxy for mas01;

    Sample IDF config:

    idf:
      fuel:
        network:
          upstream_proxy:
            address: 10.0.2.2
            port: 3128

    JIRA: FUEL-317

    Change-Id: I12be815e1b4564227fb09c20ce06cd71e7d433b6
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 02345dc..9308f98 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 02345dc455b538960ef9a2cee9acbc8e4ec60fb1
+Subproject commit 9308f98d759e4f934b4fa11533e4cec6da36cd3c