Add headers to certain test files

[turkeylurkey]

ManagedBeanTest.java
DependencyInjectionTest.java

/*******************************************************************************
 * Copyright (c) 2021, 2023 IBM Corporation and others.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/