Bump secure_headers from 5.0.1 to 5.0.2
Bump secure_headers from 5.0.1 to 5.0.2

Bumps [secure_headers](https://github.com/twitter/secureheaders) from 5.0.1 to 5.0.2.
- [Changelog](https://github.com/twitter/secureheaders/blob/master/CHANGELOG.md)
- [Commits](https://github.com/twitter/secureheaders/compare/v5.0.1...v5.0.2)
ministryofjustice/prison-visits-public,ministryofjustice/prison-visits-public,ministryofjustice/prison-visits-public,ministryofjustice/prison-visits-public