async fn scan_bucket_task(
    bucket: String,
    source_id: GlobalId,
    glob: Option<GlobMatcher>,
    aws_config: AwsConfig,
    aws_external_id_prefix: Option<AwsExternalIdPrefix>,
    tx: Sender<Result<KeyInfo, S3Error>>,
    base_metrics: SourceBaseMetrics,
    secrets_reader: Arc<dyn SecretsReader>
)