server.requestTimeout didn't work
## Describe the bug

**Node.js version:**
v18.3.0

**OS version:** 
ubuntu 22.04 arm64

**Description:** <!-- A clear and concise description of what the bug is. -->

After 5 minutes i received an error.
server.requestTimeout didn't work.

The ```http.server``` timeouts have changed in Node.js v18. The ```headersTimeout``` is set to 60000 milliseconds (60 seconds), and ```requestTimeout``` is set to 300000 milliseconds (5 minutes) by default. The ```headersTimeout``` is the time that is allowed for an HTTP request header to be parsed. The ```requestTimeout`` is the timeout used for an HTTP request.

## Actual behavior

<!-- Write actual behavior here. -->

## Expected behavior

<!-- Write expected behavior here. -->

## Code to reproduce
```
      const app =  new Koa();
      let server = await app.listen(1234);
      server.requestTimeout = 100 * 60 * 1000;
```
<!-- Share code to reproduce here inside a code formatted block, gist, or a repository we can clone to reproduce. -->

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## Checklist

- [x] I have searched through GitHub issues for similar issues.
- [x] I have completely read through the README and documentation.
- [x] I have tested my code with the latest version of Node.js and this package and confirmed it is still not working.
