Update git submodules

* Update docs/submodules/promise from branch 'stable/euphrates'
  - Merge "API/interface mapping table ETSI NFV vs Blazar" into stable/euphrates
  - API/interface mapping table ETSI NFV vs Blazar

    Change-Id: Id775c53405cf3aa42aaa439344846d07cd2ae2d4
    Signed-off-by: Gerald Kunzmann <kunzmann@docomolab-euro.com>
    (cherry picked from commit ac9bf70e774ab43a140c2c065a682b73f4dd6c16)

diff --git a/docs/submodules/promise b/docs/submodules/promise
index 76c4e4a..7a860dd 160000 (submodule)
--- a/docs/submodules/promise
+++ b/docs/submodules/promise
@@ -1 +1 @@
-Subproject commit 76c4e4a0bdde64bc36ad4bd0bdbeeb1251d3f4b8
+Subproject commit 7a860ddb028df13fd96b4869026ee0b73c61c753