code: private String getSeleniumConfigFilePath() {
          LOGGER.entering();
  
          String result = null;
          InstanceType type = getType();
  
          if (type.equals(InstanceType.SELENIUM_NODE)) {
              result = NODE_CONFIG_FILE;
              if (commands.contains(NODE_CONFIG_ARG)) {
                  result = commands.get(commands.indexOf(NODE_CONFIG_ARG) + 1);
              }
          }
          if (type.equals(InstanceType.SELENIUM_HUB)) {
              result = HUB_CONFIG_FILE;
              if (commands.contains(HUB_CONFIG_ARG)) {
                  result = commands.get(commands.indexOf(HUB_CONFIG_ARG) + 1);
              }
          }
          LOGGER.exiting(result);
          return result;
      }
docs: Get the config file path for the instance represented by this launcher.
  
  @return the config file path or <code>null</code> if no config file was specified