Avoid emojis in container image manifests and improve some labels

[anbrsap]

Problem

We use JFrog Artifactory to mirror Tekton container images for our internal consumption.

When trying to push

ghcr.io/tektoncd/pipeline/resolvers-ff86b24f130c42b88983d3c13993056d:v1.3.2

to Artifactory, the manifest is rejected (message manifest invalid).

It turned out that Artifactory doesn't like the emoji in the images' label org.opencontainers.image.description:

{
    …
    "config": {
        "Labels": {
            "maintainer": "Tekton Authors \u003ctekton-dev@googlegroups.com\u003e",
            "org.opencontainers.image.created": "2025-08-04T01:03:40.106Z",
            "org.opencontainers.image.description": "This repo holds configuration for infrastructure used across the tektoncd org 🏗️",
            "org.opencontainers.image.licenses": "Apache-2.0",
            "org.opencontainers.image.revision": "1a662374f274c695aacac56042cdb3dffa58ead7",
            "org.opencontainers.image.source": "https://github.com/tektoncd/pipeline",
            "org.opencontainers.image.title": "plumbing",
            "org.opencontainers.image.url": "https://github.com/tektoncd/plumbing",
            "org.opencontainers.image.version": "nightly"
        },
        …
    }
}

The labels are inherited from the base image originating from this plumbing repo:

ghcr.io/tektoncd/plumbing/tini-git@sha256:2c18f0b3ed4394e27068b5c70bb55419797e8fc743d8ea9e0c2766001b36b5b4

Also note that the labels org.opencontainers.image.description and org.opencontainers.image.title don't make sense, as they relate to GitHub repo github.com/tektoncd/plumbing/ as a whole, but should be specific to the image (see GitHub workflow).

Proposal

1. Avoid emojis in image manifests.

   Although the image manifests are valid according to the OCI Image Spec, Artifactory currently doesn't accept them and thus prevents us to mirror this Tekton image. We will discuss the issue with JFrog to get it resolved. But as this process may take a while, we kindly ask to remove the emoji.

2. Set image-specific values for the following labels:

   • org.opencontainers.image.description
   • org.opencontainers.image.title

[afrittoli]

Thanks @anbrsap for reporting this issue.
We use ko to build the images and we inherited this problem from it.

I filed ko-build/ko#1395 which was fixed earlier this year - hopefully pulling in a new version of ko will solve the issue.