Add links for SSP prod and staging environments

docusaurus.config.js

@@ -129,7 +129,7 @@ module.exports = {
           label: 'Self-Service-Portal',
           items: [
             {
-              label: 'Testumgebung',
+              label: 'Öffentliche Testumgebung',
               href: 'https://portal.auth-testing.fit-connect.fitko.dev/'
             },
             {