Converted `with-react-hook-form` example to TypeScript as it is pointed out in the contributing docs that examples
should be converted to TS.
- updated dependencies
- fixed/added types where necessary
## 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: Balázs Orbán <18369201+balazsorban44@users.noreply.github.com>
