Simulate tracking of security updates on a branch based on snapshots of Debian testing
_Originally created by @intrigeri on [#14823 (Redmine)](https://public-redmine-archive.tails.boum.org/code/issues/14823)_
### Attachments
* [security-tracker-overlay.diff](https://redmine.tails.boum.org/code/attachments/download/1910/security-tracker-overlay.diff)
Parent Task: tails/tails#12615
issue