feat(i18n): update Finnish translations [skip ci]

Currently translated at 32.5% (84 of 258 strings)

Co-authored-by: Jiri Nakola <github@nakola.fi>
Translate-URL: https://hosted.weblate.org/projects/discord-tickets/bot/fi/
Translation: Discord Tickets/Bot

src/i18n/fi.yml

@@ -9,6 +9,7 @@ commands:
         title: ❌ Virhe
       pinned:
         description: Viesti on kiinnitetty.
+        title: ✅ Kiinnitetty viesti
     create:
       name: Luo tiketti viestistä
   slash: