Async mode not compatible with Redis logical databases

[davidor]

The async-redis client does not support Redis logical databases. That means that it does not work properly on environments that have for example, the main db in redis://redis-backend:6379/0 and the queues in redis://redis-backend:6379/1: https://github.com/3scale/3scale-operator/blob/master/pkg/3scale/amp/auto-generated-templates/amp/amp.yml

Ref: https://github.com/socketry/async-redis/issues/15