Fix wrong state of clockShouldBeCentered when

notification is being added or removed

Bug: 332610423
Bug: 339465026
Flag: NONE bugfix
Test: manual test removing notification, observe clock moves to the
center; adding delayed notification to LS, observe clock moves left;
adding pulsing notification in AOD, observe clock moves left, and then
when pulsing notification disappears, clock moves back to center.
atest KeyguardClockInteractorTest, KeyguardClockViewModelTest, ClockSectionTest

Change-Id: I81ab731cbb310e2952aa1fbf1f80d0841797718e