site: fix build warning for #5646

package.json

@@ -133,7 +133,6 @@
     "react-dom": "^15.0.0",
     "react-github-button": "^0.1.1",
     "react-intl": "^2.0.1",
-    "react-router-dom": "^4.1.1",
     "react-sublime-video": "^0.2.0",
     "react-test-renderer": "^15.5.4",
     "reqwest": "^2.0.5",

site/bisheng.config.js

@@ -60,6 +60,10 @@ module.exports = {
       'react-router': 'react-router/umd/ReactRouter',
     };
 
+    config.externals = {
+      'react-router-dom': 'ReactRouterDOM',
+    };
+
     config.babel.plugins.push([
       require.resolve('babel-plugin-transform-runtime'),
       {