How do you run A/B tests for your iOS app icon in App Store Connect?

Apple’s documentation indicates that iOS now supports A/B testing for app icons, but I haven’t been able to get it working.

My app already includes alternate icons within the same binary, yet when I try to set up an A/B test in App Store Connect, there’s no option to change the icon-only screenshots can be updated in a new treatment.

How do you run A/B tests for your iOS app icon in App Store Connect?
 
 
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