No feedback when checking on checklist if potential spam was detected

What goes wrong

I was trying to check the checklist on #29170 (closed) however it's silently failing. If I refresh, it would still show as-if checked, so I thought it's checked. However in fact they're not checked. If I hit hard refresh (cmd+shift+r) then it would properly show that they're not checked. I was puzzled, so I just tried to edit the issue directly.

When I tried to submit my changes, it showed me:

Anti-spam verification

We detected potential spam in the issue. Please solve the reCAPTCHA to proceed.

And I could just check that I am not a robot and continue. Now I understand why it's not working by checking on the checkboxes.

This is fine, but we need feedback that why it's not changing through.

Proposal

Show a captcha when an update fails, when checking a checkbox per https://gitlab.com/gitlab-org/gitlab-ce/issues/29483#note_43096123

/cc @rymai