How to pass `CleanCSS` options via `minifyCSS`?

I'm trying to pass [Clean CSS](https://github.com/clean-css/clean-css#formatting-options) options via the `minifyCSS` property, according to the [docs](https://github.com/clean-css/clean-css#formatting-options), I should be able to pass:

```js
minifyCSS: {
format: {
semicolonAfterLastProperty: false
}
}
```

But it has not affect. What am I missing?

Start by tracing how the minifyCSS property handles the documented Clean CSS format options, then compare that path with the linked Clean CSS formatting-options documentation. Done means the semicolonAfterLastProperty setting changes the generated CSS as expected.

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