在heroku中部署mern应用程序，出现以下错误

如何解决在heroku中部署mern应用程序，出现以下错误

npm 错误！在 bloggers_den@1.0.0 启动脚本失败。
npm 错误！这可能不是 npm 的问题。上面可能有额外的日志输出。

任何帮助将不胜感激，

应用程序日志

2021-07-06T05:33:29.357332+00:00 app[web.1]: npm ERR！ blog-mern@1.0.0 开始：node server.js
2021-07-06T05:33:29.357496+00:00 app[web.1]: npm ERR！退出状态 1
2021-07-06T05:33:29.357639+00:00 应用程序[web.1]: npm ERR！
2021-07-06T05:33:29.357716+00:00 app[web.1]: npm ERR！ blog-mern@1.0.0 启动脚本失败。
2021-07-06T05:33:29.357838+00:00 app[web.1]: npm ERR！这可能不是 npm 的问题。上面可能有额外的日志输出。
2021-07-06T05:33:29.366753+00:00 应用程序[web.1]:
2021-07-06T05:33:29.370697+00:00 app[web.1]: npm ERR！可以在以下位置找到此运行的完整日志：
2021-07-06T05:33:29.370868+00:00 app[web.1]: npm ERR！ /app/.npm/_logs/2021-07-06T05_33_29_358Z-debug.log
2021-07-06T05:33:29.443928+00:00 heroku[web.1]：进程退出状态为 1
2021-07-06T05:33:29.564352+00:00 heroku[web.1]：状态从开始变为崩溃

server/package.json

{
  "name": "blog-mern","version": "1.0.0","description": "","main": "server.js","scripts": {
    "start": "node server.js","server": "nodemon server.js","client": "cd client && npm run start","server-install": "npm install","client-install": "cd client && npm install","install-all": "concurrently \"npm run server-install\" \"npm run client-install\"","dev": "concurrently \"npm run server\" \"npm run client\"","heroku-postbuild": "cd client && npm install && npm run build"
  },"keywords": [],"author": "","license": "ISC","dependencies": {
    "bcrypt": "^5.0.1","concurrently": "^6.2.0","dotenv": "^10.0.0","express": "^4.17.1","gitignore": "^0.6.0","mongoose": "^5.12.14","multer": "^1.4.2","nodemon": "^2.0.7","path": "^0.12.7"
  }
}

客户端/package.json

{
  "name": "client","version": "0.1.0","private": true,"dependencies": {
    "@testing-library/jest-dom": "^5.14.1","@testing-library/react": "^11.2.7","@testing-library/user-event": "^12.8.3","axios": "^0.21.1","react": "^17.0.2","react-dom": "^17.0.2","react-router-dom": "^5.2.0","react-scripts": "4.0.3","web-vitals": "^1.1.2"
  },"scripts": {
    "start": "react-scripts start","build": "react-scripts build","test": "react-scripts test","eject": "react-scripts eject"
  },"eslintConfig": {
    "extends": [
      "react-app","react-app/jest"
    ]
  },"browserslist": {
    "production": [
      ">0.2%","not dead","not op_mini all"
    ],"development": [
      "last 1 chrome version","last 1 firefox version","last 1 safari version"
    ]
  },"proxy": "http://localhost:5000/api/" 
}

文件夹结构：

Blog-mern
客户文件夹
添加服务器文件夹