Bump xos libraries to version 4.0.0

Change-Id: Ic9cde0c71aa018f40882953b849d0ae0a7342754
diff --git a/xos/synchronizer/config.yaml b/xos/synchronizer/config.yaml
index 647efdc..2026942 100644
--- a/xos/synchronizer/config.yaml
+++ b/xos/synchronizer/config.yaml
@@ -15,7 +15,7 @@
 
 
 name: tt-workflow-driver
-core_version: ">=2.2.1"
+core_version: ">=4.0.0"
 required_models:
   - TtWorkflowDriverService
   - TtWorkflowDriverServiceInstance