How to use the @aws-cdk/aws-ecr.Repository.fromRepositoryName function in @aws-cdk/aws-ecr

constructor(parent: cdk.App, name: string, props: TriviaBackendStackProps) {
    super(parent, name, props);

    // Network infrastructure
    const vpc = new Vpc(this, 'VPC', { maxAzs: 2 });
    const cluster = new Cluster(this, 'Cluster', {
      clusterName: props.domainName.replace(/\./g, '-'),
      vpc
    });

    // Configuration parameters
    const domainZone = HostedZone.fromLookup(this, 'Zone', { domainName: props.domainZone });
    const imageRepo = Repository.fromRepositoryName(this, 'Repo', 'reinvent-trivia-backend');
    const tag = (process.env.IMAGE_TAG) ? process.env.IMAGE_TAG : 'latest';
    const image = ContainerImage.fromEcrRepository(imageRepo, tag)

    // Lookup pre-existing TLS certificate
    const certificateArn = StringParameter.fromStringParameterAttributes(this, 'CertArnParameter', {
      parameterName: 'CertificateArn-' + props.domainName
    }).stringValue;
    const certificate = Certificate.fromCertificateArn(this, 'Cert', certificateArn);

    // Fargate service + load balancer
    new ApplicationLoadBalancedFargateService(this, 'Service', {
      cluster,
      taskImageOptions: { image },
      desiredCount: 3,
      domainName: props.domainName,
      domainZone,