Fix clippy::unnecessary_map_or lint (#228)

Use `is_some_and` instead.

examples/vello_editor/src/text.rs

@@ -96,7 +96,7 @@ impl Editor {
     }
 
     pub fn cursor_blink(&mut self) {
-        self.cursor_visible = self.start_time.map_or(false, |start_time| {
+        self.cursor_visible = self.start_time.is_some_and(|start_time| {
             let elapsed = Instant::now().duration_since(start_time);
             (elapsed.as_millis() / self.blink_period.as_millis()) % 2 == 0
         });