build: include scss files in releases

* Includes the SCSS files in releases. This has been accidentally disabled in PR angular#3443

Author: devversion

tools/gulp/tasks/components.ts

@@ -22,6 +22,7 @@ const tsconfigPath = path.join(COMPONENTS_DIR, 'tsconfig.json');
 /** Asset files to be added to the components output. */
 const assetFiles = [
   path.join(COMPONENTS_DIR, '**/*.html'),
+  path.join(COMPONENTS_DIR, '**/*.scss'),
   path.join(COMPONENTS_DIR, 'package.json'),
   path.join(PROJECT_ROOT, 'README.md'),
   path.join(PROJECT_ROOT, 'LICENSE'),