[new release] Ortac 0.6.0
This new release comes with three improvements:
- Make search for returned value description more flexible
[\#291](https://github.com/ocaml-gospel/ortac/pull/291)
- Fix generation of the `QCheck.Fn.apply` identifier
[\#288](https://github.com/ocaml-gospel/ortac/pull/288)
- Improve failure message in case of out of domain failure
[\#287](https://github.com/ocaml-gospel/ortac/pull/287)