Update git submodules

* Update docs/submodules/domino from branch 'stable/danube'
  - Adding Labels

    Labels serve as anchors/ refs when referenced from other documents
    This patch adds labels to docs/*/*/index.rst

    Change-Id: Ic47af71d73c89cf09f9803b67ecab6dfbc8d6874
    Signed-off-by: ShubhamRathi <shubhamiiitbackup@gmail.com>
    (cherry picked from commit d7a964fbf1775a60461d6f43b1fda4a32eb7cfff)

diff --git a/docs/submodules/domino b/docs/submodules/domino
index 5c20eaf..915987c 160000 (submodule)
--- a/docs/submodules/domino
+++ b/docs/submodules/domino
@@ -1 +1 @@
-Subproject commit 5c20eafdd017777d87f12a233bcbca096d8deae3
+Subproject commit 915987ceffbd35b61013e2aec57b9a53384d2de7