Update git submodules

* Update docs/submodules/functest from branch 'stable/euphrates'
  - Remove tempest_custom from testcases configs

    Change-Id: I1237eaada5257a8c01753837a5820d840b51bff1
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit a8f1d8ea374c9538b1d7a223116d8d7d9b783c89)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 82f5223..7a1e0df 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 82f52235de1d6ebfc4a54f4fc40c8b8aa8fa44e0
+Subproject commit 7a1e0df15bdd7a88c0e6df769b933e063e2359fe