Try to update MimaFilters

It seems to not like scala.caps, even though it is experimental.

Author: odersky

library/src/scala/caps.scala

@@ -2,8 +2,7 @@ package scala
 
 import annotation.experimental
 
-@experimental
-object caps:
+@experimental object caps:
 
   /** If argument is of type `cs T`, converts to type `box cs T`. This
    *  avoids the error that would be raised when boxing `*`.

project/MiMaFilters.scala

@@ -4,5 +4,6 @@ import com.typesafe.tools.mima.core._
 object MiMaFilters {
   val Library: Seq[ProblemFilter] = Seq(
     ProblemFilters.exclude[MissingClassProblem]("scala.annotation.internal.MappedAlternative"),
+    ProblemFilters.exclude[MissingClassProblem]("scala.caps"),
   )
 }