webpack をインストールして練習してたらエラーが出た。

Question

https://qiita.com/ochiochi/items/efdaa0ae7d8c972c8103　[リンク内容](https://qiita.com/ochiochi/items/efdaa0ae7d8c972c8103)

こちらのサイトでwebpackの練習をしてたらこんなエラーが出た。描き間違いかと思ったらそうではなく何が原因かよくわからない。多分バージョンとの差異で起きたと思う。

ts_tutorial % npm start npm ERR! missing script: start

npm ERR! A complete log of this run can be found in:
npm ERR! /Users/yosikiokada/.npm/_logs/2021-12-14T03_43_31_458Z-debug.log

2021-12-14T03_43_31_458Z-debug.log
0 info it worked if it ends with ok
1 verbose cli [ '/usr/local/bin/node', '/usr/local/bin/npm', 'start' ]
2 info using npm@6.14.14
3 info using node@v14.17.5
4 verbose stack Error: missing script: start
4 verbose stack     at run (/usr/local/lib/node_modules/npm/lib/run-script.js:155:19)
4 verbose stack     at /usr/local/lib/node_modules/npm/lib/run-script.js:63:5
4 verbose stack     at /usr/local/lib/node_modules/npm/node_modules/read-package-json/read-json.js:116:5
4 verbose stack     at /usr/local/lib/node_modules/npm/node_modules/read-package-json/read-json.js:436:5
4 verbose stack     at checkBinReferences_ (/usr/local/lib/node_modules/npm/node_modules/read-package-json/read-json.js:391:45)
4 verbose stack     at final (/usr/local/lib/node_modules/npm/node_modules/read-package-json/read-json.js:434:3)
4 verbose stack     at then (/usr/local/lib/node_modules/npm/node_modules/read-package-json/read-json.js:161:5)
4 verbose stack     at ReadFileContext.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/read-package-json/read-json.js:350:20)
4 verbose stack     at ReadFileContext.callback (/usr/local/lib/node_modules/npm/node_modules/graceful-fs/graceful-fs.js:123:16)
4 verbose stack     at FSReqCallback.readFileAfterOpen [as oncomplete] (fs.js:282:13)
5 verbose cwd /Users/yosikiokada/ts_tutorial
6 verbose Darwin 21.1.0
7 verbose argv "/usr/local/bin/node" "/usr/local/bin/npm" "start"
8 verbose node v14.17.5
9 verbose npm  v6.14.14
10 error missing script: start
11 verbose exit [ 1, true ]

2021-12-14T03_43_31_458Z-debug.log

{
  "name": "ts_tutorial",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "ts-loader": "^9.2.6",
    "typescript": "^4.5.4",
    "webpack": "^5.65.0",
    "webpack-cli": "^4.9.1",
    "webpack-dev-server": "^4.6.0"
  }
}

package.json