Update debugging.md (--dev -> --save-dev for npm) (#39998)

Reference:
https://docs.npmjs.com/specifying-dependencies-and-devdependencies-in-a-package-json-file#adding-dependencies-to-a-packagejson-file-from-the-command-line

## Documentation / Examples

- [x] Make sure the linting passes by running `pnpm lint`
- [x] The examples guidelines are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)

Co-authored-by: JJ Kasper <jj@jjsweb.site>

docs/advanced-features/debugging.md

@@ -90,7 +90,7 @@ Debugging server-side code here works much like debugging client-side code with
 
 ### Debugging on Windows
 
-Windows users may run into an issue when using `NODE_OPTIONS='--inspect'` as that syntax is not supported on Windows platforms. To get around this, install the [`cross-env`](https://www.npmjs.com/package/cross-env) package as a development dependency (`--dev` with NPM or `-D` for Yarn) and replace the `dev` script with the following.
+Windows users may run into an issue when using `NODE_OPTIONS='--inspect'` as that syntax is not supported on Windows platforms. To get around this, install the [`cross-env`](https://www.npmjs.com/package/cross-env) package as a development dependency (`-D` with `npm` and `yarn`) and replace the `dev` script with the following.
 
 ```json
 "dev": "cross-env NODE_OPTIONS='--inspect' next dev",