Add backwards compat for compat/server commonjs entry

Author: marvinhagemeister

compat/server.js

@@ -1,17 +1,14 @@
 /* eslint-disable */
 var renderToString;
 try {
-	renderToString = dep(require('preact-render-to-string'));
+	const mod = require('preact-render-to-string');
+	renderToString = mod.default || mod.renderToString || mod;
 } catch (e) {
 	throw Error(
 		'renderToString() error: missing "preact-render-to-string" dependency.'
 	);
 }
 
-function dep(obj) {
-	return obj['default'] || obj;
-}
-
 module.exports = {
 	renderToString: renderToString,
 	renderToStaticMarkup: renderToString