text: Title: Add unit tests for the `__repr__` method of the EndpointNode class
  Body: ## Unit Test
  
  ### Description
  
  Add unit tests for the `__repr__` method of the **EndpointNode** class: https://github.com/scanapi/scanapi/blob/main/scanapi/tree/endpoint_node.py#L55
  
  [ScanAPI Writing Tests Documentation](https://github.com/scanapi/scanapi/wiki/Writing-Tests)