JIRA macro is not handling error correctly when JIRA server is returning 401

Difficult to reproduce, but I think it's more related to the JIRA server version and also the server configuration.

It seems that in some case JIRA is also returning a code 401 (which is more correct than 400) when there are some authentication issues.

This issue is to fix this. We would need to handle the error code 401 in the same way than the generic error code 400.