Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Armband: Disable CI triggers for stable branch"
  - Armband: Disable CI triggers for stable branch

    - rename "danube" to "euphrates";
    - disable "euphrates", to be enabled when ready;

    Change-Id: Id4932986e19c664b28749d0b6926d825ea632250
    Signed-off-by: Alexandru Nemes <alexandru.nemes@enea.com>
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 054cc9c..e186165 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 054cc9c27668ccd18d970ee0c88138178301478b
+Subproject commit e186165e98458b4343507d89b1b606cdf7343a4d