Bumped version to 3.0.0-M1.
Bumped version to 3.0.0-M1.

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