style: Update class name for copy button

Author: Adebesin-Cell

app/pages/[...package].vue

@@ -455,7 +455,7 @@ function handleClick(event: MouseEvent) {
               <button
                 type="button"
                 @click="copyPkgName()"
-                class="absolute z-20 left-0 top-full inline-flex items-center gap-1 px-2 py-1 rounded border text-xs font-mono whitespace-nowrap text-fg-muted bg-bg border-border opacity-0 -translate-y-1 pointer-events-none transition-all duration-150 group-hover:opacity-100 group-hover:translate-y-0 group-hover:pointer-events-auto focus-visible:opacity-100 focus-visible:translate-y-0 focus-visible:pointer-events-auto hover:text-fg focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-fg/40"
+                class="copy-button absolute z-20 left-0 top-full inline-flex items-center gap-1 px-2 py-1 rounded border text-xs font-mono whitespace-nowrap text-fg-muted bg-bg border-border opacity-0 -translate-y-1 pointer-events-none transition-all duration-150 group-hover:opacity-100 group-hover:translate-y-0 group-hover:pointer-events-auto focus-visible:opacity-100 focus-visible:translate-y-0 focus-visible:pointer-events-auto hover:text-fg focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-fg/40"
                 :aria-label="$t('package.copy_name')"
               >
                 <span class="i-carbon:copy w-3.5 h-3.5" aria-hidden="true" />