test: use ESM syntax in tailwind config (#494)

Author: sapphi-red

playground/tailwind/tailwind.config.js

@@ -1,6 +1,11 @@
-/** @type {import('tailwindcss').Config} */
+import { fileURLToPath } from 'node:url'
+import { dirname } from 'node:path'
+
+const __filename = fileURLToPath(import.meta.url)
+const __dirname = dirname(__filename)
 
-module.exports = {
+/** @type {import('tailwindcss').Config} */
+export default {
   content: [__dirname + '/**/*.vue'],
   theme: {
     extend: {},