Reduce code duplication related to CSV

[thiessenp-cds]

Some tech debt:

Merge the related code for formatting CSV currently in (and possibly other places):

• DownloadCSVWithGroups
• DownloadCSV

Also the code to download a file could be exported to a util function:

    const url = URL.createObjectURL(blob);
    const a = document.createElement("a");
    a.href = url;
    a.download = slugify(fileName) + "." + extension};
    a.click();
    URL.revokeObjectURL(url);