Add @Override annotations to test sources

Issue: SPR-10129

spring-beans/src/test/java/com/foo/ComponentNamespaceHandler.java

@@ -3,6 +3,7 @@ package com.foo;
 import org.springframework.beans.factory.xml.NamespaceHandlerSupport;
 
 public class ComponentNamespaceHandler extends NamespaceHandlerSupport {
+	@Override
 	public void init() {
 		registerBeanDefinitionParser("component",
 				new ComponentBeanDefinitionParser());