modify imageScan Attribute of ECR in CDK

I have a private ECR imported in CDK: import { Repository } from 'aws-cdk-lib/aws-ecr'; const cdkEcrRepo = Repository.fromRepositoryName(this, 'cdkEcrRepo ', 'my_existing_repo');

Now I want to change the attribute imageScanOnPush. Not sure, how I can sett this Attribute to a new value?