Helm S3 plugin

[bezdomniy]

Hi,
Would you consider including the helm-s3 plugin in this layer? - https://github.com/hypnoglow/helm-s3?

This plugin is already recommended in the AWS documentation for Helm repos on S3.

This would allow use to use private Helm repos in S3. Also, since this layer is included in the eks blueprints project, it will naturally flow through to that project.