How to correctly log in to AWS Elastic Container Registry on Windows command line
The Elastic Container Registry (ECR) is a Docker container registry for use while deploying containers to AWS ECS. It is convenient and relatively easy to use. AWS helpfully supplies command strings to log in to ECR from the command line so you can publish container images with docker push. But the supplied command line for Windows doesn't work right, and needlessly relies on a tool that seems to not be very useful.