Update VERSION and XOS parent container

Change-Id: I60af1b284d2a245f1bcf88121a47d2498b53eddf
diff --git a/Dockerfile.synchronizer b/Dockerfile.synchronizer
index bcd1dcb..717fabe 100644
--- a/Dockerfile.synchronizer
+++ b/Dockerfile.synchronizer
@@ -16,7 +16,7 @@
 
 # xosproject/onos-synchronizer
 
-FROM xosproject/xos-synchronizer-base:2.1.4
+FROM xosproject/xos-synchronizer-base:2.1.12
 
 COPY xos/synchronizer /opt/xos/synchronizers/onos
 COPY VERSION /opt/xos/synchronizers/onos/