Global Ajax error handler

What does this MR do?

Introduces a new global Ajax error handler to show a flash warning about the error detail of XHR requests which failed with status code 404 and 500

Are there points in the code the reviewer needs to double check?

Double check the wording.

Why was this MR needed?

A global solution for the problem in the #17880 (closed)

What are the relevant issue numbers?

Fixes #17880 (closed)

Screenshots (if relevant)

For requests failed with 404 - 500

For requests failed with 401