Feature request: support `docker.io/*` images to use auth config from `~/.docker/config.json`

Version: org.testcontainers:testcontainers-bom:1.16.0

This works fine:

new GenericContainer<>("amazon/dynamodb-local:1.16.0")

I've been seeing more recommendations to prefer fully qualified docker images (e.g. podman), so I switched to:

new GenericContainer<>("docker.io/amazon/dynamodb-local:1.16.0")

And then errors started occurring during my CI build.

I eventually figured out that the auth config was not being picked up:

[Test worker] DEBUG org.testcontainers.shaded.com.github.dockerjava.core.command.AbstrDockerCmd - Cmd: docker.io/amazon/dynamodb-local:1.16.0
[Test worker] DEBUG org.testcontainers.images.AbstractImagePullPolicy - Using locally available and not pulling image: docker.io/amazon/dynamodb-local:1.16.0
[Test worker] INFO 🐳 [docker.io/amazon/dynamodb-local:1.16.0] - Creating container for image: docker.io/amazon/dynamodb-local:1.16.0
[Test worker] DEBUG org.testcontainers.utility.RegistryAuthLocator - Looking up auth config for image: docker.io/amazon/dynamodb-local:1.16.0 at registry: docker.io
[Test worker] DEBUG org.testcontainers.utility.RegistryAuthLocator - RegistryAuthLocator has configFile: /home/builder/.docker/config.json (exists) and commandPathPrefix: 
[Test worker] DEBUG org.testcontainers.utility.RegistryAuthLocator - registryName [docker.io] for dockerImageName [docker.io/amazon/dynamodb-local:1.16.0]
[Test worker] DEBUG org.testcontainers.utility.RegistryAuthLocator - No matching Auth Configs - falling back to defaultAuthConfig [null]

So I switched to index.docker.io, and it worked.

new GenericContainer<>("index.docker.io/amazon/dynamodb-local:1.16.0"):

[Test worker] DEBUG org.testcontainers.shaded.com.github.dockerjava.core.command.AbstrDockerCmd - Cmd: index.docker.io/amazon/dynamodb-local:1.16.0
[Test worker] DEBUG org.testcontainers.images.AbstractImagePullPolicy - Using locally available and not pulling image: index.docker.io/amazon/dynamodb-local:1.16.0
[Test worker] INFO 🐳 [index.docker.io/amazon/dynamodb-local:1.16.0] - Creating container for image: index.docker.io/amazon/dynamodb-local:1.16.0
[Test worker] DEBUG org.testcontainers.dockerclient.AuthDelegatingDockerClientConfig - Delegate call to effectiveAuthConfig failed with cause: 'Invalid repository name, try "amazon/dynamodb-local" instead'. Resolution of auth config will continue using RegistryAuthLocator.
[Test worker] DEBUG org.testcontainers.utility.RegistryAuthLocator - Looking up auth config for image: index.docker.io/amazon/dynamodb-local:1.16.0 at registry: index.docker.io
[Test worker] DEBUG org.testcontainers.utility.RegistryAuthLocator - Cached auth found: [AuthConfig{username=redacted, password=hidden non-blank value, auth=hidden non-blank value, email=null, registryAddress=https://index.docker.io/v1/, registryToken=blank}]

However, this is out of line with the docker cli, which does read from the ~/.docker/config.json.

If I change the https://index.docker.io/v1/ auth value and try to pull via:

docker -D pull docker.io/amazon/dynamodb-local:1.16.0

It fails with:

Error response from daemon: Head "https://registry-1.docker.io/v2/amazon/dynamodb-local/manifests/1.16.0": unauthorized: incorrect username or password

Start by tracing RegistryAuthLocator and AuthDelegatingDockerClientConfig, the components named in the logs, and compare how docker.io and index.docker.io are resolved. Done means credentials from ~/.docker/config.json are used when pulling images qualified with docker.io, with tests covering that image form.