Adding delay in OLT deletion

Change-Id: I461597855424c17d4635f10da82abe68a4d9009f
diff --git a/Dockerfile.synchronizer b/Dockerfile.synchronizer
index 4f64e57..270ba1a 100644
--- a/Dockerfile.synchronizer
+++ b/Dockerfile.synchronizer
@@ -16,7 +16,7 @@
 
 # xosproject/volt-synchronizer
 
-FROM xosproject/xos-synchronizer-base:master
+FROM xosproject/xos-synchronizer-base:2.1.4
 
 COPY xos/synchronizer /opt/xos/synchronizers/volt
 COPY VERSION /opt/xos/synchronizers/volt/