Add reader endpoint for DB clusters when creating AWS::SecretsManager::SecretTargetAttachment

When creating a DB cluster (ie: Aurora Mysql) with autorotated secrets manager credentials, and attaching connection data using AWS::SecretsManager::SecretTargetAttachment, it is missing the replicas read-only endpoint.

It would be nice to include it under some readersHost key.

Is it possible? Where should I ask for it?