Investigate impact of `data object`

[alexvanyo]

Kotlin 1.7.20 introduced a new data object variant of an object, as documented here:
https://kotlinlang.org/docs/whatsnew1720.html#improved-string-representations-for-singletons-and-sealed-class-hierarchies-with-data-objects

Whether this works out of the box or needs additional handling needs to be investigated.