$ npm init react-app test-app리액트 프로젝트를 생성하고.. $ npm install node-sass@4.14.1 classnames react-icons --save-dev위 명령어를 실행해서 node-sass 외 2개의 패키지를 설치하려고 했는데, PS C:\dev\todo-app> npm install node-sass@4.14.1 classnames react-icons --save-dev npm WARN deprecated har-validator@5.1.5: this library is no longer supported npm WARN deprecated uuid@3.4.0: Please upgrade to version 7 or higher. Older version..