renderUnexpandableClump(auditRefs, groupDefinitions) {
    const clumpElement = this.dom.createElement('div');
    const elements = this._renderGroupedAudits(auditRefs, groupDefinitions);
    elements.forEach(elem => clumpElement.append(elem));
    return clumpElement;
  }
Take a set of audits, group them if they have groups, then render in a top-level
clump that can't be expanded/collapsed.
@param {Array<LH.ReportResult.AuditRef>} auditRefs
@param {Object<string, LH.Result.ReportGroup>} groupDefinitions
@return {Element}