/usr/share/seccomp/policygroups/ubuntu-core/16.04/timezone-management is in ubuntu-core-security-seccomp 16.04.15.1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # Description: Can manage timezones directly separate from 'config ubuntu-core'.
# Usage: reserved
|