Remove redundant prefresh dependency in with-preact example (#23567)
Remove redundant prefresh dependency in with-preact example (#23567)



The package `next-plugin-preact` [already contains](https://github.com/preactjs/next-plugin-preact/blob/38cfb182ddd4720ac5f8ea885929e4c1423cc267/packages/next-plugin-preact/package.json#L25) the dependency `@prefresh/next` so it shouldn't be explicitly installed.

## Documentation / Examples

- [x] Make sure the linting passes

JeromeFitz/next.js,zeit/next.js,azukaru/next.js,azukaru/next.js,JeromeFitz/next.js,flybayer/next.js,flybayer/next.js,zeit/next.js,JeromeFitz/next.js,azukaru/next.js,JeromeFitz/next.js,azukaru/next.js,flybayer/next.js,flybayer/next.js,zeit/next.js