SEBA-324 reverse field numbers for manytoone relations

Change-Id: I9caef4161e7a9c75d27fc48c5259219f955bad31
diff --git a/Dockerfile.synchronizer b/Dockerfile.synchronizer
index ad10365..eb597c9 100644
--- a/Dockerfile.synchronizer
+++ b/Dockerfile.synchronizer
@@ -16,7 +16,7 @@
 
 # xosproject/att-workflow-driver-synchronizer
 
-FROM xosproject/xos-synchronizer-base:2.1.20
+FROM xosproject/xos-synchronizer-base:2.1.21
 
 COPY xos/synchronizer /opt/xos/synchronizers/att-workflow-driver
 COPY VERSION /opt/xos/synchronizers/att-workflow-driver/