License "GPL-2.0+" is a deprecated SPDX license identifier: 3.x

When running composer validatein the terminal, it throws a warning.

./composer.json is valid, but with a few warnings See https://getcomposer.org/doc/04-schema.md for details on the schema License "GPL-2.0+" is a deprecated SPDX license identifier, use "GPL-2.0-or-later" instead

Alter the composer.json file to remove this warning. License "GPL-2.0+" is a deprecated SPDX license identifier, use "GPL-2.0-or-later" instead.