[Tunnelbroker] add missing error logs for notifs

Summary:
While investigating ENG-9925 I discovered there are a couple more errors that worth logging

Depends on D13969

Test Plan:
Not really sure what is the best way to test it - maybe @will have some ideas.

On APNs:

1. Notif works
2. Update the code to send notif with random priority -> fails with BadPriority

On web:

1. Notif works
2. Triggering error is complicated because we use lib, so just reading the code as we use the same approach as for others

Reviewers: will, bartek

Reviewed By: will

Subscribers: ashoat, tomek, will

Differential Revision: https://phab.comm.dev/D13970