public IActionResult GerarCSVNewsletter()
{
var news = _newsletterRepository.ObterTodosNewsletter();
StringBuilder sb = new StringBuilder();
foreach (var email in news)
{
sb.AppendLine(email.Email);
}
byte[] buffer = Encoding.ASCII.GetBytes(sb.ToString());
return(File(buffer, "text/csv", $"newsletter.csv"));
}