Update license text

Author: soimkim

hooks/hook-fosslight_reuse.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 # Copyright (c) 2021 LG Electronics Inc.
-# SPDX-License-Identifier: Apache-2.0
+# SPDX-License-Identifier: GPL-3.0-only
 from PyInstaller.utils.hooks import collect_all
 
 datas, binaries, hiddenimports = collect_all('fosslight_reuse')