message: [tests] improve error message when a deploy fails
  improve error message
diff: @@ -88,7 +88,9 @@ async function nowDeploy(bodies, randomness, uploadNowJson) {
  const { readyState } = deployment;
  if (readyState === 'ERROR') {
  logWithinTest('state is ERROR, throwing');
  - const error = new Error(`State of https://${deploymentUrl} is ERROR`);
  + const error = new Error(
  + `State of https://${deploymentUrl} is ERROR: ${deployment.errorMessage}`
  + );
  error.deployment = deployment;
  throw error;
  }
  