Consume ECS client from ecs-agent module in agent module

[danehlim]

Summary

In the agent module, consume the ECS client defined in ecs-agent module.

Implementation details

• Replace all ECS client and corresponding mocks usages with the ECS client and corresponding mocks defined in ecs-agent module and update tests accordingly where necessary
• Make current NewContainerMetadataGetter and NewTaskMetadataGetter functions defined in agent/api/metadata_getter.go private as they are not to be used outside of the agent module's api package
• Write ToECSAgent translation methods for agent module level TaskStateChange, ContainerStateChange, and AttachmentStateChange state change types that convert to the state change types defined in the ecs-agent module
  • NOTE: Struct ProtocolBindIP and helper functions buildManagedAgentStateChangePayload and buildContainerStateChangePayload introduced as part of this pull request in agent/api/statechange.go are based off the components with the same names currently defined in agent/api/ecsclient/client.go
• Define new utils function Int64PtrToIntPtr in ecs-agent/utils/utils.go for use in ToECSAgent translation method
• In ecs-agent/acs/session/session.go, refactor session struct field discoverEndpointClient of type api.ECSDiscoverEndpointSDK such that it is renamed to struct field ecsClient with type ecs.ECSClient instead
  • Type api.ECSDiscoverEndpointSDK is currently being used in ACS session but is no longer necessary now that there exists an ECS client in the ecs-agent module that we are consuming in agent module as part of this pull request
• Add a unit test in agent/api/task/task_test.go to assert that container port zero will explicitly not be included in the set of container ports that are exposed for a container
• Delete the following files as they are no longer being used:
  • agent/api/ecsclient/client.go
  • agent/api/ecsclient/client_test.go
  • agent/api/ecsclient/retry_handler.go
  • agent/api/ecsclient/retry_handler_test.go
  • agent/api/ecsclient/utils.go
  • agent/api/ecsclient/utils_amd64_test.go
  • agent/api/ecsclient/utils_arm64_test.go
  • agent/api/generate_mocks.go
  • agent/api/interface.go
  • agent/api/mocks/api_mocks.go
  • ecs-agent/api/generate_mocks.go
  • ecs-agent/api/interface.go
  • ecs-agent/api/mocks/api_mocks.go

Testing

Unit, integration, and functional tests.

New tests cover the changes: yes

Description for the changelog

Consume ECS client from ecs-agent module in agent module

Does this PR include breaking model changes? If so, Have you added transformation functions?
No

Licensing

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

[fierlion]

approve (post merge)