PollingWatchService fails on ignored filter test on Windows

[eed3si9n]

See for example https://github.com/sbt/io/actions/runs/17044606710/job/48360607495?pr=431

[info] - should watch a directory for file creation *** FAILED ***
[info]   EventMonitorSpec.this.watchTest(parentDir, sbt.internal.io.EventMonitorSpec.pathFilter(created.toPath()), sbt.internal.io.EventMonitorSpec.contains(created.toPath()))(sbt.io.IO.write(created, "foo", sbt.io.IO.write$default$3, sbt.io.IO.write$default$4)) was false (SourceModificationWatchSpec.scala:65)

[eed3si9n]

Seems to have been fixed by #439