Update `English` translation

Currently translated at 100.0% (613 of 613 strings)

Translation: Wiki-Bot/Discord
Translate-URL: https://translate.wikibot.de/projects/wiki-bot/discord/en/

i18n/en.json

@@ -658,6 +658,7 @@
         "MediaWiki": "Requires at least $1 for full functionality, found `$2`.",
         "notice": "Limited functionality",
         "pause": "I'm currently paused on this server.",
+        "slow": "Sorry, I seem to be a bit slow right now.",
         "text": [
             "I'm fully functional!",
             "I'm still alive!",