Add border line to resources which have children

[a2ush]

Issue #, if available:

There is an issue where the border is not displayed even for resources that have children.

Description of changes:

If a resource has children, the border line will be drawn.

Resources:
  SampleFargateCluster:
    Type: AWS::ECS::Cluster

Resources:
  SampleFargateCluster:
    Type: AWS::ECS::Cluster

  SampleFargateService:
    Type: AWS::ECS::Service
    Properties:
      Cluster: !Ref SampleFargateCluster

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