Enabled PropCheckerAssertingAsyncSpec.scala under Scala 3 build.
Enabled PropCheckerAssertingAsyncSpec.scala under Scala 3 build.

cheeseng/scalatest,scalatest/scalatest,cheeseng/scalatest,dotty-staging/scalatest,dotty-staging/scalatest,scalatest/scalatest,scalatest/scalatest,dotty-staging/scalatest,cheeseng/scalatest