Match any user pkgs for headless sys user mode

In headless system user mode a package might not be installed in the
system user. Since the config list is only loaded and matched against
packages for the system user, we need to handle the case where a package
might exist on the system but not be installed for the system user.

Bug: 241469882
Test: atest NotificationListenersTest
Change-Id: I3e225047846658479d00d4089b8864860ef0c274