Archiving project doesn't clear associated `todos`

Summary

Todos from archived projects are still showing up in my dashboard/todos tab.

Steps to reproduce

• find an active project,
  • active as in there are open issues and/or merge requests, some assigned to you.
• go to settings, mark the projet Archived.
• in the todos section the issues and assigned MR's are still listed.

Example Project

NA, this is observed on the CE version; I'm not self-hosting or anything.

What is the current bug behavior?

The Todo's are still listed.

What is the expected correct behavior?

When archiving a project it says that the project will not be available in searches, which I took to mean that it'll clear up the workspaces of all the team members.

Clearing the associated TODO's as well would help maintain cleanliness of people's workspaces so it doesn't get too crowded.

Relevant logs and/or screenshots

NA

Output of checks

This bug happens on GitLab.com

Possible fixes

(If you can, link to the line of code that might be responsible for the problem)