Issue: Hashmap child annotation serialization unit test failing

Fix: Changed the string against which unit testing is being done. There is a odataType string member variable in Base class, which is overriden in one of the class which is being serialized. Hence @odata.type string should also be present in the serialized string for the object.

Author: deepak2016

src/test/java/com/microsoft/graph/serializer/AdditionalDataTests.java

@@ -73,6 +73,6 @@ public void testHashMapChildAnnotationData() {
 
 		String serializedObject = serializer.serializeObject(task);
 
-		assertEquals("{\"assignments\":{\"id\":{\"orderHint\":\"!\",\"additionalData\":\"additionalValue\"}}}", serializedObject);
+		assertEquals("{\"assignments\":{\"id\":{\"@odata.type\":\"#microsoft.graph.plannerAssignment\",\"orderHint\":\"!\",\"additionalData\":\"additionalValue\"}},\"@odata.type\":\"#microsoft.graph.plannerTask\"}", serializedObject);
 	}
 }