fix: switch output naming to cjs

Author: art049

packages/benchmark.js/package.json

@@ -3,7 +3,7 @@
   "version": "0.0.0",
   "description": "",
   "keywords": [],
-  "main": "dist/index.umd.js",
+  "main": "dist/index.cjs.js",
   "module": "dist/index.es5.js",
   "typings": "dist/index.d.ts",
   "files": [