auth: switch back to the default i18next namespace

We match based on the tag name now and not on the namespace,
so revert this again so it's consistent with the other packages

packages/auth/src/i18n.js

 import {createInstance as _createInstance, setOverrides} from '@dbp-toolkit/common/i18next.js';
 
-import de from './i18n/de/dbp-auth.json';
-import en from './i18n/en/dbp-auth.json';
+import de from './i18n/de/translation.json';
+import en from './i18n/en/translation.json';
 
 export function createInstance() {
-    return _createInstance({en: en, de: de}, 'de', 'en', 'dbp-auth');
+    return _createInstance({en: en, de: de}, 'de', 'en');
 }
 
 export {setOverrides};
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