Add default interop to tailwindcss/plugin

Fixes Skypack version of tailwindcss/plugin

Author: bradlc

plugin.js

@@ -1,3 +1,3 @@
-const createPlugin = require('./lib/util/createPlugin').default
+const createPlugin = require('./lib/util/createPlugin')
 
-module.exports = createPlugin
+module.exports = (createPlugin.__esModule ? createPlugin : { default: createPlugin }).default