fix missing header

Author: hu-ahmed

things/service/src/main/java/org/eclipse/ditto/things/service/persistence/actors/strategies/commands/UpdateThingDefinitionStrategy.java

@@ -1,3 +1,15 @@
+/*
+ * Copyright (c) 2025 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package org.eclipse.ditto.things.service.persistence.actors.strategies.commands;
 
 import java.time.Instant;