Using sm-docker too often triggers throttling on dockerhub

[absynthe]

After running sm-docker for 3-4 times in the same hour I get the error:
toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit

[absynthe]

Can be fixed by using use public.ecr.aws images instead of docker ones. This should be added to the docs.