Cannot remove project level 'to do' label, which doesn't exist in the project.

Summary

I cannot delete the project label "to-do", since it doesn't exist in the project anymore.

It's still appearing on all of these issues.

Steps to reproduce

Try and remove the to do label from one of the issues in the link above.

Example Project

link

Relevant logs and/or screenshots

Output of checks

This bug happens on GitLab.com