Well…I’m familiar with container registries but there is a new paradigm that is being worked on… an artifact registry. The idea is the same as a container (image) registry…store versions of files/configs/images, etc and distribute it to your containers. This would create a new standard that would be supported across all docker implementations and would allow you to update the artifacts separately from the application itself.
You can read more about this from Steve Lasker, a Program Manager on the Azure team.