<?php
/**
 * @file
 * Contains \Drupal\AppConsole\Command\GeneratorEntityContentCommand.
 */

namespace Drupal\AppConsole\Command;

class GeneratorEntityContentCommand extends GeneratorEntityCommand {

  protected function configure()
  {
    parent::configure();
  }
}

<?php
/**
 * @file
 * Contains \Drupal\AppConsole\Command\GeneratorEntityContentCommand.
 */

namespace Drupal\AppConsole\Command;

class GeneratorEntityContentCommand extends GeneratorEntityCommand {

  protected function configure()
  {
    $this->setEntityType('EntityContent');
    $this->setCommandName('generate:entity:content');
    parent::configure();
  }
}

Use new setter methods at parent class
Use new setter methods at parent class
