Docker errors similar to the following may indicate that the user running the build job doesn't have
a minimum of the Guest role in the specified Dependency Proxy group:
```plaintext
ERROR: gitlab.example.com:443/group1/dependency_proxy/containers/alpine:latest: not found
failed to solve with frontend dockerfile.v0: failed to create LLB definition: gitlab.example.com:443/group1/dependency_proxy/containers/alpine:latest: not found