Prior to this commit, the `ErrorController` would override the original
error response status if the error map cannot be written due to content
negotiation with the HTTP client. In that case, the error handling
infrastructure returns a `406 Not Acceptable` response.
This commit improves the `ErrorController` so that
`HttpMediaTypeNotAcceptableException` instances thrown by that
controller are not returned as is but instead we write the error
response with an empty body and the original HTTP error status.
Fixes gh-19522
cc154bbefb