Update git submodules

* Update docs/submodules/armband from branch 'stable/euphrates'
  - docs: Sync latest Fuel updates

    Change-Id: I88e2a3f59ccada34dcc88e0b4d864721e6d3242e
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
    (cherry picked from commit be80704371c4cba5d8a0f88d08b5ea3dd02e889f)

diff --git a/docs/submodules/armband b/docs/submodules/armband
index 006db47..777eb4c 160000 (submodule)
--- a/docs/submodules/armband
+++ b/docs/submodules/armband
@@ -1 +1 @@
-Subproject commit 006db47f3a00933570a8446c7dc9fc723f5e7c5f
+Subproject commit 777eb4c1bcab2062afcdc65a0575cba268de562d