Liberty default HttpAuthenticationMechanisms do not call HttpMessageContext.responseUnauthorized

[Zech-Hein]

Describe the bug
A HttpMessageContextWrapper can override the responseUnauthorized method to enrich the response, by adding headers for example. Liberty's HttpAuthenticationMechanisms do not call HttpMessageContext.responseUnauthorized.

Steps to Reproduce

1. Have an authentication mechanism decorator used in application that uses a HttpMessageContextWrapper that overwrites the responseUnauthorized method to enrich the response to an unauthorized request.
2. Submit an unauthorized request.
3. Observe the responseUnauthorized method will not be called

Expected behavior
Liberty default HttpAuthenticationMechanisms should call HttpMessageContext.responseUnauthorized for unauthorized requests.

Diagnostic information:

• OpenLiberty Version: [-22.0.0.12]
• Affected feature(s) [appSecurity-3.0/4.0/5.0]