Bug when use ref in extensions

### Runtime

Node.js

### Runtime version

v22.14.0

### Module version

v17.13.3

### Last module version without issue

_No response_

### Used with

_No response_

### Any other relevant information

Documentation: https://joi.dev/api/?v=17.13.3#extensions

This part in documentation don't work correctly.

```
a: custom.million().round().dividable(Joi.ref('b')),
```

### What are you trying to achieve or the steps to reproduce?

Create an schema using the example of the documentation.

### What was the result you got?

Error: **args.q is `undefined`**

### What result did you expect?

The argument must come with the correct value of the reference.