When pushing to a container registry, you need to maintain the respective credentials in your Jenkins credentials store:
Kaniko expects a Docker `config.json` file containing the credential information for registries.
You can create it like explained in the Docker Success Center in the articale about [How to generate a new auth in the config.json file](https://success.docker.com/article/generate-new-auth-in-config-json-file).
Please copy this file and upload it to your Jenkins for example<br/>