Fix cloudinary default quality to use q_auto (#19694)
Fix cloudinary default quality to use q_auto (#19694)

The [default loader](https://github.com/vercel/next.js/blob/17b91e7c76711308707bc8ab3308376af98170e6/packages/next/client/image.tsx#L488) and [imgix loader](https://docs.imgix.com/apis/rendering/format/q) use a quality of 75 if none is specified on the Image component.

This PR does something similar for the cloudinary loader by utilizing `q_auto`, but it should yield even better results.

> This setting can significantly reduce the file size without any degradation noticeable to the human eye, and without the need for you to individually analyze every image.

https://cloudinary.com/documentation/image_optimization#use_q_auto_automatic_quality_and_encoding

### Example
- [Before](https://res.cloudinary.com/demo/image/upload/woman.jpg) - 583KB
- [After](https://res.cloudinary.com/demo/image/upload/q_auto/woman.jpg) - 46KB
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