Fix lint

Author: gaearon

packages/react-scripts/scripts/start.js

@@ -203,7 +203,7 @@ function addMiddleware(devServer) {
     var hpm = httpProxyMiddleware(pathname => mayProxy.test(pathname), {
       target: proxy,
       logLevel: 'silent',
-      onProxyReq: function(proxyReq, req, res) {
+      onProxyReq: function(proxyReq) {
         // Browers may send Origin headers even with same-origin
         // requests. To prevent CORS issues, we have to change
         // the Origin to match the target URL.