ECS now supports cgroups v2

[fendent]

Summary

ECS now supports cgroups v2 and no longer needs to block the install in this case.

Reference:
aws/containers-roadmap#1535
aws/amazon-ecs-agent#3127

Implementation details

I removed the flow logic that bails if it detects cgroups v2.

Testing

I have been able to successfully run the install script and get a properly running ECS agent in docker on a cgroups v2 debian bullseye docker container.

New tests cover the changes: no

Description for the changelog

Bug - Install script no longer fails on systems using cgroups v2

Licensing

This contribution is under the terms of the Apache 2.0 License: yes

[fendent]

Will changes made to ecs-anwyhere-install.sh in this repo reflect on the script in the public S3 bucket that the ECS console has you use to register external instances?

[sparrc]

Will changes made to ecs-anwyhere-install.sh in this repo reflect on the script in the public S3 bucket that the ECS console has you use to register external instances?

Yep! it will be updated after our next ecs agent/init release, which should happen within 2-4 weeks

[sparrc]

Thanks for this! lgtm