Success banner shown after request failed

[nilbus]

Description

During the performance issues, I happened to have Chrome Inspector's Network tab open and saw that the update_phone_number_completion request failed with a CORS error, probably just due to the site outage since it normally works fine. However, the UI lied and showed a green success banner.

Expected Behavior

Error message if any fetch/XHR request fails.

Current Behavior

1. Access to XMLHttpRequest at 'https://api.crisiscleanup.org/phone_outbound/update_phone_number_completion' from origin 'https://crisiscleanup.org' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
2. A success message in a green banner is displayed with the text, "Phone number removed from queue."