Popups/Calendar is not coming over the overlay

**Description**

If we put a calendar/Datepicker such as ShowDatePicker button inside the overlay, the calendar popups behind the overlay which is not accessible. We have to close the overlay to access the calendar.

**To Reproduce**
Steps to reproduce the behavior:
1. Implement 'ShowOverlay' in an empty screen
2. Add ShowDatePicker inside that overlay (overlay being the parent of ShowDatePicker)
3. Try to open ShowDatePicker

**Expected behaviour**
The expected behaviour of the similar situation should be that the calendar stacks on top of the overlay and is accessible also.

**Screenshots**

**Version (please complete the following information):**
- Flutter Version: 3.3.9
- OS: Chrome (macOS 14)
- OverlaySupport Version : latest

**Additional context**
Add any other context about the problem here.