Access Denied to gcr.io/gcp-elixir Image During App Engine Deployment

# Access Request: GCP Elixir Docker Image

## Problem
Unable to pull Docker image `gcr.io/gcp-elixir/runtime/ubuntu18/generate-dockerfile:2022-03-25-173415` during Google App Engine deployment.

## Error
```
Permission "artifactregistry.repositories.downloadArtifacts" denied on resource "projects/gcp-elixir/locations/us/repositories/gcr.io"
```

## What We Need
- Information on how to access this image, which we believe should be publicly available
- Information on project status: Is the gcp-elixir project still maintained?

## Context
This error occurs during our App Engine deployment process and may be related to the migration from Container Registry to Artifact Registry. We're trying to understand why we're encountering permission issues for an image that should be publicly accessible.

If the project is deprecated or the access method has changed, please advise on recommended migration paths or alternative approaches.

Thank you.