Update webpack.config.js

Disable AMD and solve swagger client issues since there is no intention of supporting it:

facebook#3247 (comment)

Author: martnu

packages/react-scripts/config/webpack.config.js

@@ -299,7 +299,7 @@ module.exports = function(webpackEnv) {
       strictExportPresence: true,
       rules: [
         // Disable require.ensure as it's not a standard language feature.
-        { parser: { requireEnsure: false } },
+        { parser: { requireEnsure: false, amd: false } },
 
         // First, run the linter.
         // It's important to do this before Babel processes the JS.