If KotlinTest `Gen` module depended on `arrow-core...

# arrow-contributors

[raulraja]

If KotlinTest Gen module depended on arrow-core we can just derive anything we need in the arrow side because it would allows us to provide instances for Gen including automatic derivation for data classes, etc. https://github.com/arrow-kt/kotlintest/blob/rr-kotlin-test-arrow-revamp/kotlintest-assertions/src/main/kotlin/io/kotlintest/properties/Gen.kt#L57