Fix BubbleExtractor not looking up activity info in a user-based way

Use package manager to look up activity info with the userId for
the notification, instead of using package manager based on current
context which doesn't work for HSUM.

Flag: EXEMPT bug fix
Test: atest BubbleExtractorTest NotificationManagerServiceTest
Test: manual - make a secondary user and send an intent-based bubble
             - ensure the bubble button is on the notification
Bug: 362181768
Change-Id: I5359bc395f06cbb5d0706f81fa2be1a56efc63d5