前提・実現したいこと

現在Laravelにてポートフォリオを作成しており、ようやくデプロイの段階まで来ました。

https://ayaka-weblog.com/programming/laravel/laravel-heroku/
↑
こちらの方の記事を参考にしながらmysqlの環境変数などを入れていき
git push heroku masterをしたところ以下のエラーが出てしまいました。

発生している問題・エラーメッセージ

remote: Compressing source files... done.
remote: Building source:
remote: 
remote: -----> Building on the Heroku-20 stack
remote: -----> Using buildpacks:
remote:        1. heroku/nodejs
remote:        2. heroku/php
remote: -----> Node.js app detected
remote: parse error: Expected another key-value pair at line 12, column 5
remote:  !     Unable to parse package.json
remote: 
remote: 
remote: -----> Build failed
remote: 
remote: We're sorry this build is failing! You can troubleshoot common issues here:
remote: https://devcenter.heroku.com/articles/troubleshooting-node-deploys
remote: 
remote: If you're stuck, please submit a ticket so we can help:
remote: https://help.heroku.com/
remote: 
remote: Love,
remote: Heroku
remote: 
remote:  !     Push rejected, failed to compile Node.js app.
remote: 
remote:  !     Push failed
remote:  !
remote:  ! ## Warning - The same version of this code has already been built: 8f5b86cc98a4608bc93eb28e0a3fce9d80a38ce5
remote:  !
remote:  ! We have detected that you have triggered a build from source code with version 8f5b86cc98a4608bc93eb28e0a3fce9d80a38ce5
remote:  ! at least twice. One common cause of this behavior is attempting to deploy code from a different branch.
remote:  !
remote:  ! If you are developing on a branch and deploying via git you must run:
remote:  !
remote:  !     git push heroku <branchname>:main
remote:  !
remote:  ! This article goes into details on the behavior:
remote:  !   https://devcenter.heroku.com/articles/duplicate-build-version
remote: 
remote: Verifying deploy...
remote: 
remote: !	Push rejected to your-hero-tky.
remote: 
To https://git.heroku.com/your-hero-tky.git
 ! [remote rejected] master -> main (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/your-hero-tky.git'
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