Fix #11885: disable flaky idempotency test on Windows

Author: liufengyun

tests/idempotency/IdempotencyCheck.scala

@@ -6,7 +6,12 @@ import java.util.stream.Stream as JStream
 import scala.collection.JavaConverters.*
 
 object IdempotencyCheck {
-  val blacklisted = Set(
+  val flakytests =
+    if scala.util.Properties.isWin
+    then Set(s"pos{JFile.separator}i6507b")
+    else Set.empty
+
+  val blacklisted = flakytests ++ Set(
     // No fix needed. Bridges on collections in different order. Second one in scala2 order.
     s"pos{JFile.separator}Map{JFile.separator}scala{JFile.separator}collection{JFile.separator}immutable/Map",
     s"pos{JFile.separator}Map{JFile.separator}scala{JFile.separator}collection{JFile.separator}immutable{JFile.separator}AbstractMap",