AWS: list Aurora supported PostgreSQL versions

[jerome@jeroboam] > aws rds describe-db-engine-versions --engine aurora-postgresql --region eu-west-1
[
...
        {
            "Engine": "aurora-postgresql", 
            "DBParameterGroupFamily": "aurora-postgresql10", 
            "SupportsLogExportsToCloudwatchLogs": false, 
            "SupportsReadReplica": false, 
            "DBEngineDescription": "Aurora (PostgreSQL)", 
            "SupportedEngineModes": [
                "provisioned"
            ], 
            "EngineVersion": "10.6", 
            "DBEngineVersionDescription": "Aurora PostgreSQL (compatible with PostgreSQL 10.6)", 
            "ValidUpgradeTarget": []
        }
    ]