Docker container image labels

[na4ma4]

Dependabot can follow docker dependencies if the images have the org.opencontainers.image.source label.

But it may be worth adding additional labels just for completeness, the docker/metadata-action can generate most of them automatically.

Example container image with labels:

$ docker inspect --format='{{json .Config.Labels}}' mariadb:10.4 | jq .
{
  "org.opencontainers.image.authors": "MariaDB Community",
  "org.opencontainers.image.base.name": "docker.io/library/ubuntu:focal",
  "org.opencontainers.image.description": "MariaDB Database for relational SQL",
  "org.opencontainers.image.documentation": "https://hub.docker.com/_/mariadb/",
  "org.opencontainers.image.licenses": "GPL-2.0",
  "org.opencontainers.image.ref.name": "ubuntu",
  "org.opencontainers.image.source": "https://github.com/MariaDB/mariadb-docker",
  "org.opencontainers.image.title": "MariaDB Database",
  "org.opencontainers.image.url": "https://github.com/MariaDB/mariadb-docker",
  "org.opencontainers.image.vendor": "MariaDB Community",
  "org.opencontainers.image.version": "10.4.29"
}

[davidcoutadeur]

Should be ok with #866