Fix dockercore/engine-pull-all-test-fixture

[rumpl]

Description

This image is used in our integration tests but it contains an error:

$ docker buildx imagetools inspect dockercore/engine-pull-all-test-fixture --raw | jq 
{
  "schemaVersion": 2,
  "mediaType": "application/vnd.docker.distribution.manifest.list.v2+json",
  "manifests": [
    {
      "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
      "size": 424,
      "digest": "sha256:1db73f3610a525e10f80c62326bfbab538d9eda3c893d3cdd4b91f65ed711998",
      "platform": {
        "architecture": "amd64",
        "os": "linux"
      }
    },
    {
      "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
      "size": 427,
      "digest": "sha256:acd186e17ca720587dc000dd8217e8a8c201f39f470bb088fde5132492676f99",
      "platform": {
        "architecture": "arm64",
        "os": "linux",
        "variant": "v8"
      }
    },
    {
      "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
      "size": 427,
      "digest": "sha256:8116ed3458950def2a355933273866d586c93776cf16abb84347bfd727c9f714",
      "platform": {
        "architecture": "arm",
        "os": "linux",
        "variant": "v7"
      }
    },
    {
      "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
      "size": 427,
      "digest": "sha256:c051972bddc3b34420e3792e2d0d35cbf6b7d4b8d9918b740294a8e7c3eb8a04",
      "platform": {
        "architecture": "ppc64le",
        "os": "linux"
      }
    },
    {
      "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
      "size": 427,
      "digest": "sha256:cf4d184f7ca8072d5047725af02a081b4e49b96936fd45446d8b8cee62f7eb83",
      "platform": {
        "architecture": "s390x",
        "os": "linux"
      }
    }
  ]
}

The linux/amd64 manifest has a size of 424 but looking at the actual manifest size we get 524:

$ docker buildx imagetools inspect dockercore/engine-pull-all-test-fixture@sha256:1db73f3610a525e10f80c62326bfbab538d9eda3c893d3cdd4b91f65ed711998 --raw | wc -c   
524

This difference in sizes makes some of the tests fail with containerd