Add support for fips endpoints

This issue is for the ECR Push and Pull tasks.

I am trying to push to an image to the ECR repository using the FIPS compliant endpoint, but the task doesn't appear to expose the option to use this endpoint. From [the documentation](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/cmd-ecs-cli-push.html) that I have read for the ecs cli it appears there is a flag option that should be able to use the `--use-fips` but that flag doesn't appear to be exposed anywhere in the tasks and there doesn't appear to be a way to add additional flags to the command used

The issue names the ECR Push and Pull tasks; start by locating their task definitions and the command construction, then compare the documented --use-fips option. Done means the relevant tasks expose this option and pass it to the ECS CLI invocation.

Written by the indexing model from the issue text.