docs: use vanity link for discord

Author: tg73

site/docs/introduction.mdx

@@ -106,7 +106,7 @@ These printers are supported through community contributions and may not be as w
 Join the discussion on discord!
 
 <p>
-	<Link to="https://discord.gg/D62e8XNeYa" className="button button--primary">
+	<Link to="https://discord.gg/RatRig" className="button button--primary">
 	Join the Unnofficial RatRig Discord Community
 	</Link>
 </p>