Download a Google Sheet to my computer as .xlsx file using app javascript

Question

everyone! I am working with App Javascript into a Google Sheet and I need to run a script to download the Worksheet to my computer with extension .xlsx I am so close, but it is missing the end.

function exportExcel() {
    /*Get your Spreadsheet */
    var ss = SpreadsheetApp.openById("sheetID");

    //*Create URL to Export as xlsx
    var url = "https://docs.google.com/feeds/download/spreadsheets/Export?key=" + ss.getId() + "&exportFormat=xlsx";

    var params = {
      method: "get",
      //*add authorization to get the file 
      headers: { "Authorization": "Bearer " + ScriptApp.getOAuthToken() },
      muteHttpExceptions: true
    };

    //* with an http query get the blob file
    var blob = UrlFetchApp.fetch(url, params).getBlob();

    //* sets the file extension 
    blob.setName("BCI Scorecard.xlsx")
    blob.name = "BCI Scorecard.xlsx"
    blob.lastModified = new Date()

    console.log(blob)
    //Send Mail with attachments 
    MailApp.sendEmail("email", "Scorecard", "This mail contains .XLSX file attached",
      { attachments: [blob] });
}

With this code, I am able to send the file attached to my email (made just for test). But what I really want is to save it in a designed path in my computer.

What is missing? I know I am close.

Thank you, Breno