Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Run tests from the new tiers"
  - Run tests from the new tiers

    It conforms with the new test tiers [1]

    [1] https://gerrit.opnfv.org/gerrit/#/c/66863/

    Change-Id: I615277c4525b6dbc24442668c5179dd34952dc43
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index d96d637..1b3b3ed 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit d96d6379d66f15cb34c95433db2922bca531bdb5
+Subproject commit 1b3b3ed8bd98fe7fb94fcc4cf46e400226cdf783