Comment 5 for bug 1800862

I installed update-notifier from bionic-proposed:
```
apt-cache policy update-notifier
update-notifier:
  Installed: 3.192.1.4
  Candidate: 3.192.1.4
  Version table:
 *** 3.192.1.4 500
        500 http://us.archive.ubuntu.com/ubuntu bionic-proposed/main amd64 Packages
```

I performed the following manual tests:
- boot, wait for update-notifier to start, manually modify the status file: notification was displayed
- reboot: at the boot no notification was displayed as expected
- reboot, manually modify the status file before login, login: notification was displayed
- boot with kernel 4.15.0-38.41-generic: a notification was displayed