Fix tests

Author: liufengyun

tests/neg/enums.scala

@@ -22,7 +22,7 @@ enum E4 {
   case C4(x: Int)
 }
 object E4 {
-  val x1: Int => E4 = C4    // error: found: C4, required: Int => E4
+  val x1: Int => E4 = C4    // ok
   val x2: Int => E4 = C4(_) // ok
 }
 

tests/pos/t3137.scala renamed to tests/neg/t3137.scala

@@ -13,5 +13,5 @@ trait AA {
 }
 
 class BB extends AA {
-  case class C(v: Int)
+  case class C(v: Int) // error
 }