Updated service to use new XOS core version: 2.1.22

Change-Id: Idbef029698be6dc4fb94dde1e0c3cfd6f4f58e81
diff --git a/Dockerfile.synchronizer b/Dockerfile.synchronizer
index 717fabe..e4cf25d 100644
--- a/Dockerfile.synchronizer
+++ b/Dockerfile.synchronizer
@@ -16,7 +16,7 @@
 
 # xosproject/onos-synchronizer
 
-FROM xosproject/xos-synchronizer-base:2.1.12
+FROM xosproject/xos-synchronizer-base:2.1.22
 
 COPY xos/synchronizer /opt/xos/synchronizers/onos
 COPY VERSION /opt/xos/synchronizers/onos/