Fix typo in v4 font-stretch utilities

Author: thecrypticace

src/pages/docs/v4-beta.mdx

@@ -1028,7 +1028,7 @@ We've added utilities for the new-ish `font-stretch` property, which helps you s
     </p>
   </div>
   <div>
-    <span class="font-medium text-sm text-slate-500 font-mono mb-3 dark:text-slate-400">font-stretch-extra-regular</span>
+    <span class="font-medium text-sm text-slate-500 font-mono mb-3 dark:text-slate-400">font-stretch-normal</span>
     <p class="text-xl font-medium [font-stretch:normal] font-[system-ui] text-slate-900 dark:text-slate-200">
       The quick brown fox jumps over the lazy dog.
     </p>