build: added browser instead of main entry again

Author: mfranzke

package.json

@@ -3,6 +3,7 @@
   "version": "1.0.0-2",
   "description": "Fast and lightweight dependency-free vanilla JavaScript polyfill for native lazy loading / the awesome loading='lazy'-attribute supported by a Service Worker.",
   "source": "./src/loading-attribute-polyfill-with-serviceworker.js",
+  "browser": "./dist/loading-attribute-polyfill-with-serviceworker.js",
   "esmodule": "./dist/loading-attribute-polyfill-with-serviceworker.modern.js",
   "module": "./dist/loading-attribute-polyfill-with-serviceworker.module.js",
   "umd:main": "./dist/loading-attribute-polyfill-with-serviceworker.umd.js",