Updated service to use new XOS core version: 2.1.25

Change-Id: If7bbb653182bf0aa65bf0db3012bedb054b7a5aa
diff --git a/Dockerfile.synchronizer b/Dockerfile.synchronizer
index e4cf25d..efc126a 100644
--- a/Dockerfile.synchronizer
+++ b/Dockerfile.synchronizer
@@ -16,7 +16,7 @@
 
 # xosproject/onos-synchronizer
 
-FROM xosproject/xos-synchronizer-base:2.1.22
+FROM xosproject/xos-synchronizer-base:2.1.25
 
 COPY xos/synchronizer /opt/xos/synchronizers/onos
 COPY VERSION /opt/xos/synchronizers/onos/