Remove handler callbacks correctly

 Use removeCallbacksAndEqualMessages when removing handler callbacks by notification key.
 If a notification was updated and then canceled during the DELAY_FORCE_REGROUP_TIME: the callback was not removed because Handler#removeCallbacksMessages would check for reference equality, which would fail because the update would create a new
 NotificationRecord with the same key.

 Also skip calling GroupHelper#onNotificationPostedWithDelay if the notification was removed during DELAY_FORCE_REGROUP_TIME.

Flag: android.service.notification.notification_force_grouping
Test: atest NotificationManagerServiceTest
Bug: 376222541
Change-Id: I651c6d094558c558153f0a4e667ce4c3874ca398