Patch create-react-app to support configuration extensions

react-scripts+3.4.1.patch

diff --git a/node_modules/react-scripts/config/webpack.config.js b/node_modules/react-scripts/config/webpack.config.js
index 25840d9..b5e210f 100644
--- a/node_modules/react-scripts/config/webpack.config.js
+++ b/node_modules/react-scripts/config/webpack.config.js
@@ -36,6 +36,7 @@ const typescriptFormatter = require('react-dev-utils/typescriptFormatter');
 const getCacheIdentifier = require('react-dev-utils/getCacheIdentifier');
 // @remove-on-eject-end
 const postcssNormalize = require('postcss-normalize');
+const extendConfig = require('../../../webpack.config.extend')

 const appPackageJson = require(paths.appPackageJson);

@@ -138,7 +139,7 @@ module.exports = function(webpackEnv) {
     return loaders;
   };

-  return {
+  return extendConfig({
     mode: isEnvProduction ? 'production' : isEnvDevelopment && 'development',
     // Stop compilation early in production
     bail: isEnvProduction,
@@ -715,5 +716,5 @@ module.exports = function(webpackEnv) {
     // Turn off performance processing because we utilize
     // our own hints via the FileSizeReporter
     performance: false,
-  };
+  }, env, { paths });
 };