Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - pharos git submodule: Bump for latest PDF adapter

    Change-Id: I658c1dfeb369adf74038abd0ce1b593d40303527
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 3a3a708..5ad2e31 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 3a3a7081c3b38ff0ec95c1c65eca152af0900fb8
+Subproject commit 5ad2e311bbc1326493386aeee4d87a9091337adf