Can't remove issues from board through the sidebar

Summary

Clicking 'Remove From Board' doesn't work for issues in milestone lists.

Steps to reproduce

1. Set up a new board;
2. Add a list for a milestone with issues in it;
3. Open the sidebar by clicking on an issue card in the milestone list, and
4. Try to remove it by clicking 'Remove from Board'.

Example Project

https://staging.gitlab.com/gitlab-org/gitlab/-/boards?milestone_title=10.0

What is the current bug behavior?

Issue remains in list

What is the expected correct behavior?

Issue is removed from list

Relevant logs and/or screenshots

instrument.js:102 TypeError: Cannot read property 'id' of undefined
    at remove_issue.vue:57
    at Array.map (<anonymous>)
    at a.buildPatchRequest (remove_issue.vue:57)
    at a.removeIssue (remove_issue.vue:27)
    at Vt (vue.esm.js:1863)
    at HTMLButtonElement.n (vue.esm.js:2188)
    at HTMLButtonElement.o._wrapper (vue.esm.js:7559)
    at HTMLButtonElement.r (helpers.js:71)

Possible fixes