Remove test dependency on native scala

[emmanaakai]

When running tests using mill without scala native set up, an error with the following stack trace occurs:

1 targets failed
morphir[2.12.18].ir.native.test.nativeClang scala.scalanative.build.BuildException: 'clang' not found in PATHor via 'LLVM_BIN' environment variable.
Please refer to (http://www.scala-native.org/en/latest/user/setup.html)
scala.scalanative.build.Discover$.$anonfun$discover$7(Discover.scala:202)
scala.Option.getOrElse(Option.scala:201)
scala.scalanative.build.Discover$.discover(Discover.scala:196)
scala.scalanative.build.Discover$.discover(Discover.scala:209)
scala.scalanative.build.Discover$.clang(Discover.scala:33)
mill.scalanativelib.worker.ScalaNativeWorkerImpl.discoverClang(ScalaNativeWorkerImpl.scala:43)
mill.scalanativelib.ScalaNativeModule.$anonfun$nativeClang$3(ScalaNativeModule.scala:150)
To Reproduce

Safe removal of scala native from the morphir-jvm project may resolve this issue

[DamianReeves]

Curious @emmanaakai (@stephengoldbaum , @AttilaMihaly ), is there still a need in your environment for Scala 2.12? Are we able to make Scala 2.13 the minimum?

[DamianReeves]

Is this issue only happening locally for you? I am not able to reproduce