code: function mapSuites(suite, totalTestsReg, config) {
    const suites = _.compact(_.map(suite.suites, subSuite => (
      mapSuites(subSuite, totalTestsReg, config)
    )));
    const toBeCleaned = Object.assign({}, suite, { suites });
    return cleanSuite(toBeCleaned, totalTestsReg, config);
  }
docs: Map over a suite, returning a cleaned suite object
  and recursively cleaning any nested suites.
  
  @param {Object} suite          Suite to map over
  @param {Object} totalTestsReg  Cumulative count of total tests registered
  @param {Integer} totalTestsReg.total
  @param {Object} config         Reporter configuration