Bump Scala baseVersion to 3.1.0-RC1.

For the upgrade to Scala.js 1.6.0, which is not a forward binary
compatible change.

Author: sjrd

project/Build.scala

@@ -65,7 +65,7 @@ object DottyJSPlugin extends AutoPlugin {
 object Build {
   val referenceVersion = "3.0.0"
 
-  val baseVersion = "3.0.3-RC1"
+  val baseVersion = "3.1.0-RC1"
 
   // Versions used by the vscode extension to create a new project
   // This should be the latest published releases.

project/MiMaFilters.scala

@@ -4,10 +4,5 @@ import com.typesafe.tools.mima.core.ProblemFilters._
 
 object MiMaFilters {
   val Library: Seq[ProblemFilter] = Seq(
-    // Internals added in 3.0.2
-    exclude[MissingClassProblem]("scala.annotation.internal.ProvisionalSuperClass"),
-
-    // New APIs marked @experimental in 3.0.2
-    exclude[MissingClassProblem]("scala.Selectable$WithoutPreciseParameterTypes")
   )
 }