Reference to a potentially unmaintained project (projectatomic/dockerfile_lint)

The project [projectatomic/dockerfile_lint](https://github.com/projectatomic/dockerfile_lint) does not have any commits to its defaul branch since 2020-07-30. Please check if the project is still maintained.

Start by locating the reference to projectatomic/dockerfile_lint in the aws/eks-best-practices repository, then inspect the linked project's recent activity and maintenance status. Done means the reference has been checked against current evidence and the issue records whether it should remain or be updated.

Written by the indexing model from the issue text.