Update `German` translation

Currently translated at 100.0% (526 of 526 strings)

Translation: Wiki-Bot/Discord
Translate-URL: https://weblate.frisk.space/projects/wiki-bot/discord/de/

i18n/de.json

@@ -405,6 +405,7 @@
         "founder": "Gründer:",
         "image": "Bild:",
         "inaccurate": "Statistiken können ungenau sein",
+        "lang": "Sprache:",
         "manager": "Wiki-Manager:",
         "name": "Vollständiger Name:",
         "no": "Nein",