feat(ecs): Ensure public IP addresses are not assigned automatically

[MarioRgzLpz]

Context

Added a new check that verifies whether Amazon ECS services are configured to automatically assign public IP addresses. The check fails if AssignPublicIP is ENABLED and passes if AssignPublicIP is DISABLED.

A public IP address is an IP address that is reachable from the internet. If you launch your Amazon ECS instances with a public IP address, then your Amazon ECS instances are reachable from the internet. Amazon ECS services should not be publicly accessible, as this may allow unintended access to your container application servers.

Description

Changed ecs_service.py to add the new Service model and two new methods to list and describe services. Added new ecs_service_no_assign_public_ip.py with respective unit tests.

Checklist

• Are there new checks included in this PR? Yes
  • If so, do we need to update permissions for the provider? No
• Review if the code is being covered by tests.
• Review if code is being documented following this specification https://github.com/google/styleguide/blob/gh-pages/pyguide.md#38-comments-and-docstrings
• Review if backport is needed.

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.