async try_join_all example

    let stmts = future::try_join_all(vec![
        client.prepare(&format!(
            "select * from {} where not_deleted = 't'",
            ManagedTargetMountRecord::table_name()
        )),
        client.prepare(&format!(
            "select * from {} where not_deleted = 't'",
            StratagemConfiguration::table_name()
        )),
        client.prepare(&format!(
            "select * from {} where not_deleted = 't'",
            LnetConfigurationRecord::table_name()
        )),
        client.prepare(&format!(
            "select * from {} where not_deleted = 't'",
            VolumeNodeRecord::table_name()
        )),
        client.prepare(&format!(
            "select * from {} where not_deleted = 't'",
            OstPoolRecord::table_name()
        )),
        client.prepare(&format!(
            "select * from {}",
            OstPoolOstsRecord::table_name()
        )),
    ])
    .await?;