Bumped up default scala version to 2.13.1, and removed commented code in scalatest.scala.
Bumped up default scala version to 2.13.1, and removed commented code in scalatest.scala.

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