docs(exporter): Update exporter.js (#5300)

Added separator parameter documentation in the formatAsCsv function

src/features/exporter/js/exporter.js

@@ -821,6 +821,7 @@
          * where each header is an object with name, width and maybe alignment
          * @param {array} exportData an array of rows, where each row is
          * an array of column data
+         * @param {string} separator a string that represents the separator to be used in the csv file
          * @returns {string} csv the formatted csv as a string
          */
         formatAsCsv: function (exportColumnHeaders, exportData, separator) {