Add missing license header to fix the build

Author: marko-bekhta

hibernate-models/src/test/java/org/hibernate/models/MultiDimensionalArrayTypeTests.java

@@ -1,3 +1,7 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright: Red Hat Inc. and Hibernate Authors
+ */
 package org.hibernate.models;
 
 import org.hibernate.models.internal.ArrayTypeDetailsImpl;