npm run prestart && npm run start fail

~/study/webpack-hot-server-example
$ npm run prestart && npm run start

> webpack-hot-server-example@1.0.0 prestart D:\study\webpack-hot-server-example
> rimraf build

> webpack-hot-server-example@1.0.0 prestart D:\study\webpack-hot-server-example
> rimraf build

> webpack-hot-server-example@1.0.0 start D:\study\webpack-hot-server-example
> webpack --watch

Invalid configuration object. Webpack has been initialised using a configuration object that does not match the API schema.
- configuration.output.path: The provided value "./build/server" is not an absolute path!
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! webpack-hot-server-example@1.0.0 start: `webpack --watch`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the webpack-hot-server-example@1.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\Administrator\AppData\Roaming\npm-cache\_logs\2020-09-28T02_38_08_003Z-debug.log