static _makeSnippetLinesArray(content, maxLineLength) {
    return content.split('\n').map((line, lineIndex) => {
      const lineNumber = lineIndex + 1;
      /** @type LH.Audit.Details.SnippetValue['lines'][0] */
      const lineDetail = {
        content: Util.truncate(line, maxLineLength),
        lineNumber,
      };
      if (line.length > maxLineLength) {
        lineDetail.truncated = true;
      }
      return lineDetail;
    });
  }
@param {string} content
@param {number} maxLineLength
@return {LH.Audit.Details.SnippetValue['lines']}