function newAthenaClient(connection) {
  configureAWS(connection);

  const athenaExpressConfig = {
    aws: AWS,
    s3: connection.athenaStagingDirectory,
    workgroup: connection.athenaWorkgroup || 'primary',
    ignoreEmpty: false,
    waitForResults: false,
  };
  return new athena.AthenaExpress(athenaExpressConfig);
}
Load Athena client.
@param {object} connection