Brief summary of the bug. What is it ? Where is it ?

Alerts can be created for % reports with thresholds outside the 0-100 range. This doesn't make sense and we should prevent this in the UI. We currently throw an error in the backend when this happens, but the error is not handled in the frontend and no error message is displayed to the user

Steps to reproduce:

Actual result:

The alert cannot be created and a generic error is shown

Expected result:

The UI prevents selection of values outside of this range. Alternatively, a useful error message is displayed when such an error occurs