Fix packageMonitor

The package monitor is supposed to check the lock screen wallpaper if it
can potentially a live wallpaper, which can be the case if
isLockscreenLiveWallpepr == true. The exclamation mark is just a misuse
of the lockscreenLiveWallpaper flag, and is most likely the reason why
bb/301073479 has not been fixed so far.

Bug: b/301073479
Test: treehugger
Change-Id: Iabc1026eff3ed0f72a08f444ecad90a95179a584