04f26a1 [mailman3] Fix the rest API on mailman

Authored and Committed by zlopez 10 months ago
    [mailman3] Fix the rest API on mailman
    
    The API didn't work and failed with 500, because the REST framework didn't know
    how to render the response. This fixes the issue.
    
    https://pagure.io/fedora-infrastructure/issue/12134
    
    Signed-off-by: Michal Konecny <mkonecny@redhat.com>