We already have stepping tests for Kotlin/JVM.
They are helpful for testing the correctness of the generated
debugging information.
They are better than line number tests in that they allow to test the
_behavior_, not the generated data. The structure of the data may change
even if the behavior stays the same. For that reason, stepping tests
are more stable.
E.g. in `x + f()` where `f` is an inline lambda, the instructions for
`+` should have the line number of that expression (while previously
they instead had the line number of the last line of the lambda).
^KT-51738 Fixed