Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[virtual] Horizon: Use v2 API instead of v3"
  - [virtual] Horizon: Use v2 API instead of v3

    JIRA: FUEL-284

    Change-Id: I821a8e79e6a23a71eae0fc0f857c1d05b30cd188
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 2a74900..90d0111 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 2a74900ecd451c939a34d53a529e802cc2250db9
+Subproject commit 90d0111f79d13a71af7952c289414474f3169abd