function richTextToPlainText(result, part, index) {
  if (index % 2 === 0) {
    result += part;
  }
  return result;
}
Converts rich text to plain text for text along lines.
@param {string} result The resulting plain text.
@param {string} part Item of the rich text array.
@param {number} index Index of the item in the rich text array.
@return {string} The resulting plain text.