MLECO-3583: Update copyright notice according to new guidelines

Change-Id: I0f057b33993e5196a60e52f4fb0c60e09693dcfe
diff --git a/download_dependencies.py b/download_dependencies.py
index dccd38d..23afe8d 100755
--- a/download_dependencies.py
+++ b/download_dependencies.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-#  Copyright (c) 2021-2022 Arm Limited. All rights reserved.
+#  SPDX-FileCopyrightText: Copyright 2021-2022 Arm Limited and/or its affiliates <open-source-office@arm.com>
 #  SPDX-License-Identifier: Apache-2.0
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");