Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Run unit tests on gerrit events"
  - Run unit tests on gerrit events

    JIRA: DOVETAIL-742

    This patch runs unit tests on gerrit events instead of hello world.

    Change-Id: I3c0fd42532871cddab1bf69f84b9ac83fc7a0cf2
    Signed-off-by: Stamatis Katsaounis <mokats@intracom-telecom.com>
    Depends-On: https://gerrit.opnfv.org/gerrit/63157

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 2875f7d..1a1c897 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 2875f7d7903099dd6c0e8e85502d0a2f0cba1496
+Subproject commit 1a1c8970989d9a4d7bb1010c8cb4d9a5be15b66f