Docker plugin fails for images using oci v1 media types

Any images that still use `application/vnd.oci.image.manifest.v1+json` and/or `application/vnd.oci.image.layer.v1.tar+gzip` (such as library/archlinux on docker hub) cause the docker plugin to error with a 404 error code, even though the image definetly exists.

Manually adding these two media types to the relevant mediaType checks and accept headers makes it work reliably for pretty much every plugin that I tested.

Start by locating the Docker plugin's mediaType checks and Accept headers, then reproduce the failure with an image using the OCI v1 media types described in the issue. Done means those images are accepted and the plugin no longer returns a 404.

Written by the indexing model from the issue text.