Back out "ESM plugin bundles"

Summary:
Original commit changeset: 2a60315dd5c0

Original Phabricator Diff: D50015827

Reviewed By: lblasa

Differential Revision: D50168201

fbshipit-source-id: 3430c37b0aa6a5e3a5ec35fb4c54f01899236173

desktop/flipper-server-core/src/server/startServer.tsx

@@ -177,13 +177,6 @@ async function startHTTPServer(
     res.end('flipper-ok');
   });
 
-  // In dev plugins are served with paths from their location on disk
-  if (process.env.NODE_ENV !== 'production') {
-    app.use(
-      express.static(config.staticPath.split('/').slice(0, -1).join('/')),
-    );
-  }
-
   app.use(express.static(config.staticPath));
 
   const server = http.createServer(app);