refactor: remove code that was needed for eject

Author: alan-agius4

packages/angular_devkit/build_angular/src/angular-cli-files/models/webpack-configs/common.ts

@@ -150,11 +150,6 @@ export function getCommonConfig(wco: WebpackConfigOptions) {
 
     const copyWebpackPluginInstance = new CopyWebpackPlugin(copyWebpackPluginPatterns,
       copyWebpackPluginOptions);
-
-    // Save options so we can use them in eject.
-    (copyWebpackPluginInstance as any)['copyWebpackPluginPatterns'] = copyWebpackPluginPatterns;
-    (copyWebpackPluginInstance as any)['copyWebpackPluginOptions'] = copyWebpackPluginOptions;
-
     extraPlugins.push(copyWebpackPluginInstance);
   }