fix(calendardatepicker): Now closes the opened picker when the contro…

…l is unloading

src/Uno.UI/UI/Xaml/Controls/CalendarView/CalendarDatePicker.Events.cs

@@ -28,5 +28,13 @@ public event TypedEventHandler<CalendarDatePicker, CalendarDatePickerDateChanged
 			add => _dateChanged += value;
 			remove => _dateChanged -= value;
 		}
+
+		private protected override void OnUnloaded()
+		{
+			// Ensure flyout is closed when the control is unloaded
+			IsCalendarOpen = false;
+
+			base.OnUnloaded();
+		}
 	}
 }