Update git submodules

* Update docs/submodules/promise from branch 'stable/euphrates'
  - Fix table formatting in api_mapping

    Change-Id: Ia76924629a450e51fc2a2bdbf7821a3c5f7a053e
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>

diff --git a/docs/submodules/promise b/docs/submodules/promise
index 7a860dd..4fce836 160000 (submodule)
--- a/docs/submodules/promise
+++ b/docs/submodules/promise
@@ -1 +1 @@
-Subproject commit 7a860ddb028df13fd96b4869026ee0b73c61c753
+Subproject commit 4fce83663cfbfc6ee7be35ca8ef5ae5c96ec56a7