Add fault-injection capability

[harishxr]

Summary

Added support to advertise fault injection capability (ecs.capability.fault-injection) to ecs agent when the required network packages are present on the host.

Implementation details

• Updated agent capabilities to include the fault inject capability.
• Added checkNetworkTooling() to check if the required network packages are available on the host for the capability to be advertised.
• Adjusted unit tests to verify fault injection capability based on available network tooling.

Testing

• Added unit tests to ensure capability is enabled only when network tooling packages are available.
• Installed iproute-tc and iptables package on the host and ran aws ecs describe-container-instances --cluster <cluster-name> --container-instances <instance-id>

{
                    "name": "ecs.capability.fault-injection"
                },

• The ecs.capability.fault-injection is enabled when the required packages are present on the host.
• If required packages are not present, following message is found in ecs.agent.log

level=warn time=2024-09-09T21:17:08Z msg="Fault injection capability not enabled: Required network tools (iptables, tc) are missing" module=agent_capability.go

New tests cover the changes: yes

Description for the changelog

• Added fault injection capability to ECS Agent.

Additional Information

Does this PR include breaking model changes? If so, Have you added transformation functions?

Does this PR include the addition of new environment variables in the README?

Licensing

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

[mye956]

You'll probably need to implement a no-op/dummy function for non-linux as well.

[mye956]

https://github.com/aws/amazon-ecs-agent/blob/master/agent/app/agent_capability_windows.go

https://github.com/aws/amazon-ecs-agent/blob/master/agent/app/agent_capability_unspecified.go

[harishxr]

Implemented in 1a3ea5b