Bump up ONOS to version 2.3.1 of yangtools

Change-Id: I96c3ce7672df6c11f9049eb8462b395b75087da2
diff --git a/drivers/microsemi/src/test/java/org/onosproject/yang/MockYangRuntimeManager.java b/drivers/microsemi/src/test/java/org/onosproject/yang/MockYangRuntimeManager.java
index 1a941e0..3bebf4c 100644
--- a/drivers/microsemi/src/test/java/org/onosproject/yang/MockYangRuntimeManager.java
+++ b/drivers/microsemi/src/test/java/org/onosproject/yang/MockYangRuntimeManager.java
@@ -130,6 +130,17 @@
         }
 
         @Override
+        public void registerAnydataSchema(Class id, Class id1) {
+            throw new UnsupportedOperationException("registerAnydataSchema() needs to be implemented");
+        }
+
+        @Override
+        public void unregisterAnydataSchema(Class id, Class id1) {
+            throw new UnsupportedOperationException("unregisterAnydataSchema() needs to be implemented");
+
+        }
+
+        @Override
         public Set<YangSerializer> getSerializers() {
             return serializerRegistry.getSerializers();
         }