Fix unsubscribe links for epics
What does this MR do and why?
Email notifications include an unsubscribe link in Epic activity. Clicking on the link while logged in was raising a 500 error (but successfully unsubscribing)
How to set up and validate locally
- Enable notifications for your own activity
- Create an epic
- Create a note on that epic
- You should receive an email with the new note creation. On the bottom, there's an unsubscribe link
- Clicking it would return a 500 error before, now it should be fixed
MR acceptance checklist
Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.
Related to #579051 (closed)