test: add optional expected events to reduce flakiness (#28)

Fixes these two flaky fails.

-
https://github.com/rolldown/notify/actions/runs/19609907135/job/56154220049
-
https://github.com/rolldown/notify/actions/runs/19609919875/job/56154246242

Author: sapphi-red

notify/src/inotify.rs

@@ -1510,6 +1510,7 @@ mod tests {
         rx.wait_ordered_exact([
             expected(&path).access_open_any().optional(),
             expected(&path).remove_folder(),
+            expected(&path).access_open_any().optional(),
         ])
         .ensure_no_tail();
         assert_eq!(
@@ -1522,6 +1523,7 @@ mod tests {
         rx.wait_ordered_exact([
             expected(&path).access_open_any().optional(),
             expected(&path).create_folder(),
+            expected(&path).access_open_any().optional(),
         ])
         .ensure_no_tail();
         assert_eq!(

notify/src/windows.rs

@@ -1076,6 +1076,7 @@ pub mod tests {
             expected(tmpdir.path()).modify_any(),
             expected(&overwriting_file).modify_any().multiple(),
             expected(&overwritten_file).remove_any(),
+            expected(tmpdir.path()).modify_any().optional(),
             expected(&overwriting_file).rename_from(),
             expected(&overwritten_file).rename_to(),
             expected(tmpdir.path()).modify_any(),