Fix timer cleanup on ComboBox unmount (#6072)

* Fix timer cleanup on ComboBox unmount

* Fix: Ensure proper timer cleanup in ComboBox on unmount

---------

Co-authored-by: Reid Barber <reid@reidbarber.com>
Co-authored-by: Yihui Liao <44729383+yihuiliao@users.noreply.github.com>

Author: 3 people

packages/@react-spectrum/combobox/src/ComboBox.tsx

@@ -278,6 +278,13 @@ const ComboBoxInput = React.forwardRef(function ComboBoxInput(props: ComboBoxInp
     lastInputValue.current = inputValue;
   }, [isLoading, showLoading, inputValue]);
 
+  useEffect(() => {
+    return () => {
+      clearTimeout(timeout.current);
+      timeout.current = null;
+    };
+  }, []);
+
   return (
     <FocusRing
       within