convert GPLv2 license to SPDX

This is part of https://fedoraproject.org/wiki/Changes/SPDX_Licenses_Phase_4

R-websocket.spec

@@ -4,10 +4,11 @@
 
 Name:             R-%{packname}
 Version:          %{packver}
-Release:          8%{?dist}
+Release:          9%{?dist}
 Summary:          'WebSocket' Client Library
 
-License:          GPLv2
+# Automatically converted from old format: GPLv2 - review is highly recommended.
+License:          GPL-2.0-only
 URL:              https://CRAN.R-project.org/package=%{packname}
 Source0:          https://cran.r-project.org/src/contrib/%{packname}_%{packver}.tar.gz
 # https://github.com/rstudio/websocket/issues/59
@@ -84,6 +85,9 @@ rm -f %{buildroot}%{rlibdir}/R.css
 
 
 %changelog
+* Mon Jul  29 2024 Miroslav Suchý <msuchy@redhat.com> - 1.4.1-9
+- convert license to SPDX
+
 * Wed Jul 17 2024 Fedora Release Engineering <releng@fedoraproject.org> - 1.4.1-8
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_41_Mass_Rebuild