Heroku 빌드팩 설정 관련 질문입니다 ㅜㅜ

안녕하세요 멘토님. 그대로 따라하다가 히로쿠에서 deploy 클릭시 다음과 같은 빌드에러가 발생합니다.

-----> Building on the Heroku-22 stack
-----> Using buildpack: heroku/nodejs
-----> App not compatible with buildpack: https://buildpack-registry.s3.amazonaws.com/buildpacks/heroku/nodejs.tgz
       
 !     ERROR: Application not supported by 'heroku/nodejs' buildpack
 !     
 !     The 'heroku/nodejs' buildpack is set on this application, but was
 !     unable to detect a Node.js codebase.
 !         
 !     A Node.js app on Heroku requires a 'package.json' at the root of
 !     the directory structure.
 !     
 !     If you are trying to deploy a Node.js application, ensure that this
 !     file is present at the top level directory. This directory has the
 !     following files:
 !     
 !     README.md
 !     shopping-mall/
 !     yarn.lock
 !         
 !     If you are trying to deploy an application written in another
 !     language, you need to change the list of buildpacks set on your
 !     Heroku app using the 'heroku buildpacks' command.
 !         
 !     For more information, refer to the following documentation:
 !     https://devcenter.heroku.com/articles/buildpacks
 !     https://devcenter.heroku.com/articles/nodejs-support#activation
       More info: https://devcenter.heroku.com/articles/buildpacks#detection-failure
 !     Push failed

참고하라는 곳을 봐도 쇼핑몰프로젝트에 어떤 빌드팩을 써야하는지 모르겠어서요 ㅜㅜ

참고: https://devcenter.heroku.com/articles/buildpacks#setting-a-buildpack-on-an-application

보아하니 Setting에서 빌드팩 추가하는 부분이 있길래 이부분에서 뭔가를 해줘야하는거 같은데, 안되네요ㅜㅜ (참고로 저는 heroku/nodejs라고 설정했었습니다.)

도와주세요 ㅜㅜ