Point to the new key.

playbooks/roles/rabbitmq/defaults/main.yml

@@ -29,7 +29,7 @@ RABBITMQ_CLUSTERED_HOSTS: []
 # option to force deletion of the mnesia dir
 rabbitmq_refresh: false
 
-rabbitmq_apt_key: "http://www.rabbitmq.com/rabbitmq-signing-key-public.asc"
+rabbitmq_apt_key: "https://www.rabbitmq.com/rabbitmq-release-signing-key.asc"
 rabbitmq_repository: "deb http://www.rabbitmq.com/debian/ testing main"
 # We mirror the deb package for rabbitmq-server because
 # nodes need to be running the same version