fix: Use custom label for CompatibilityContentUnavailableView

[facumenzella]

Motivation

This PR tries to address #4638.

Before	After

Description

For some reason, ContentUnavailableView truncates the label. I've tried using lineLimit(nil) over the Label, but that didn't work. This seems to do the trick.

fixedSize(vertical:true) forces the view to grow vertically to the needed height.

[aboedo]

Looks good to me! It does mean we have a liiitle more vertical padding now (see the screenshots) but it doesn't look wrong to my eye

[aboedo]

(approved but we should fix the linting + approve the new snapshots before merging)

[ajpallares]

I'm curious 🤔. Would it be possible to remove the if let description and keep only this?

ContentUnavailableView {
    Label {
        titleView
    } icon: {
        iconView
    }
}
description: { description }

I don't know if nil would have the same effect as EmptyView() (which is the default value for the description parameter when the parameter is not included)