Upgrade to nullability plugin 0.0.6

Closes gh-1718

Author: snicoll

gradle/plugins/gradle.properties

@@ -2,4 +2,4 @@ assertJVersion=3.25.3
 gradleVersionsPluginVersion=0.52.0
 javaFormatVersion=0.0.47
 junitVersion=5.11.0
-nullabilityPluginVersion=0.0.5
+nullabilityPluginVersion=0.0.6

spring-ws-core/src/main/java/org/springframework/ws/server/endpoint/MethodEndpoint.java

@@ -125,7 +125,7 @@ public MethodParameter getReturnType() {
 	 * @return the invocation result
 	 * @throws Exception when the method invocation results in an exception
 	 */
-	public Object invoke(Object... args) throws Exception {
+	public Object invoke(@Nullable Object... args) throws Exception {
 		Object endpoint = getBean();
 		ReflectionUtils.makeAccessible(this.method);
 		try {