Update git submodules

* Update docs/submodules/functest from branch 'stable/euphrates'
  - Add euphrates as a docker tag to the release notes

    Change-Id: I35080b3e701de6341926f86e8aa1910ef777f565
    Signed-off-by: Jose Lausuch <jalausuch@suse.com>
    (cherry picked from commit b94eea5dc2d97a5055d2a98b7b330cc52cac5649)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 50645d3..a8ee3e0 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 50645d3d21e9e724c933a8f1981e0c1d7a80f7a2
+Subproject commit a8ee3e0ce732793124a2cf2114ddcd3ccc724503