samples: remove nginxhttps sample

[Redent0r]

Merge Checklist

• Followed patch format from upstream recommendation: https://github.com/kata-containers/community/blob/main/CONTRIBUTING.md#patch-format
  • Included a single commit in a given PR - at least unless there are related commits and each makes sense as a change on its own.
• Aware about the PR to be merged using "create a merge commit" rather than "squash and merge" (or similar)
• The upstream/missing label (or upstream/not-needed) has been set on the PR.

Summary

This sample was meant to show support for pulling images with v1 manifest schema versions.

The nginxhttps image has been modified in https://hub.docker.com/r/ymqytw/nginxhttps/tags such that we are no longer able to pull it:

$ docker pull ymqytw/nginxhttps:1.5
Error response from daemon: missing signature key

We may remove this sample since schema version 1 manifests are deprecated per https://docs.docker.com/engine/deprecated/#pushing-and-pulling-with-image-manifest-v2-schema-1 : "These legacy formats should no longer be used, and users are recommended to update images to use current formats, or to upgrade to more current images". This schema version was used by old docker versions. Further OCI spec https://github.com/opencontainers/image-spec/blob/main/manifest.md#image-manifest-property-descriptions only supports schema version 2.

Test Methodology

test run: https://dev.azure.com/mariner-org/mariner/_build/results?buildId=672238&view=results

[Redent0r]

A couple of more points to remove this image:

• Schema v1 only seems to be present in some very old images (>8 years old)
• Haven't been able to find another image with v1 schema in https://hub.docker.com/search?q=nginxhttps
• We'll still be testing containerd pull in our test pipeline. We test all images twice: with default pull and with containerd pull
• If a client reports v1 image broke, we may add that image back to our test suite. Although they may also consider using a newer image, since it's deprecated by docker anyways