chore: add file header

Refs: #966

tests/administration/Administration.Service.Tests/BusinessLogic/ServiceAccountManagementTests.cs

@@ -1,3 +1,22 @@
+/********************************************************************************
+ * Copyright (c) 2024 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 Apache License, Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+
 using Org.Eclipse.TractusX.Portal.Backend.Administration.Service.BusinessLogic;
 using Org.Eclipse.TractusX.Portal.Backend.Framework.ErrorHandling;
 using Org.Eclipse.TractusX.Portal.Backend.PortalBackend.DBAccess;