aws-sdk-ruby: ECS register_task_definition validation bug (log_driver)

Issue description

I’m taking an existing valid task definition in json format, converting it to the proper casing and then resubmitting via the SDK. Only 1 validation error on submission:

2017-12-29T15:34:58.285Z 79621 TID-oumh4as1o WARN: ArgumentError: missing required parameter params[:container_definitions][0]["log_configuration"][:log_driver]

I can hack around this by either doing task['container_definitions'].first['log_configuration'][:log_driver] = 'awslogs' to explicitly set the log_driver to be a symbol or it also works if I disable validation entirely Aws::ECS::Client.new(region: 'us-east-1', validate_params: false)

Gem name (‘aws-sdk’, ‘aws-sdk-resources’ or service gems like ‘aws-sdk-s3’) and its version

    aws-sdk (2.10.105)
      aws-sdk-resources (= 2.10.105)
    aws-sdk-core (2.10.105)
      aws-sigv4 (~> 1.0)
      jmespath (~> 1.0)
    aws-sdk-resources (2.10.105)
      aws-sdk-core (= 2.10.105)
    aws-sigv4 (1.0.2)

Version of Ruby, OS environment

2.3.1 on OSX

Code snippets / steps to reproduce

• Logging definition in json

      "logConfiguration": {
        "logDriver": "awslogs",
        "options": {
          "awslogs-group": "awslogs-some-service",
          "awslogs-region": "us-east-1",
          "awslogs-stream-prefix": "some-service"
        }
      },

• Main code body

    ecs = Aws::ECS::Client.new(region: 'us-east-1')
    task = JSON.parse(File.read(task_file))
    task['containerDefinitions'].first['image'] = publish_image

    skip_transform = task['containerDefinitions'].first['logConfiguration'].delete('options')
    task.deep_transform_keys!(&:underscore).with_indifferent_access
    task['container_definitions'].first['log_configuration']['options'] = skip_transform
   
    task_revision = ecs.register_task_definition(
        {container_definitions: task['container_definitions'], family: task['family'], task_role_arn: task['task_role_arn']}
    )['task_definition']['revision']