Migrate to SPDX license

This is part of https://fedoraproject.org/wiki/Changes/SPDX_Licenses_Phase_2
PD dedication has been submitted as https://gitlab.com/fedora/legal/fedora-license-data/-/merge_requests/452

argon2.spec

@@ -21,7 +21,7 @@ Version: %{upstream_version}%{?upstream_prever:~%{upstream_prever}}
 Release: 3%{?dist}
 Summary: The password-hashing tools
 
-License: Public Domain or ASL 2.0
+License: LicenseRef-Fedora-Public-Domain OR Apache-2.0
 URL:     https://github.com/%{gh_owner}/%{gh_project}
 Source0: https://github.com/%{gh_owner}/%{gh_project}/archive/%{gh_commit}/%{gh_project}-%{upstream_version}%{?upstream_prever}-%{gh_short}.tar.gz