[drop_yui] use jenkins button

[scherler]

Testing done

before

after

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[jglick]

Not sure if this monitor even still needs to exist; quite old. So presumably untested. 🤷

[basil]

So presumably untested. 🤷

FTR we did test it in #490, and the Testing Done section there shows how to reach the page.

[scherler]

I added screenshots now