Update git submodules

* Update docs/submodules/promise from branch 'master'
  - Updated list of upstream contributions in Blazar

    Change-Id: I6ea967492ce7faf8a9f849a4129a6536e66fcd1f
    Signed-off-by: Bertrand Souville <souville@docomolab-euro.com>

diff --git a/docs/submodules/promise b/docs/submodules/promise
index a7a7034..c23e113 160000 (submodule)
--- a/docs/submodules/promise
+++ b/docs/submodules/promise
@@ -1 +1 @@
-Subproject commit a7a703420f552c0df396575e893a319cc0233ea8
+Subproject commit c23e1136d5e036476a7720ce841d73c19bcc99d7