public function toMail() : MailMessage
{
$mailMessage = (new MailMessage())->error()->subject("Important: The backups for `{$this->applicationName()}` are unhealthy")->line("The backups for `{$this->applicationName()}` on disk `{$this->diskName()}` are unhealthy.")->line($this->problemDescription());
$this->backupDestinationProperties()->each(function ($value, $name) use($mailMessage) {
$mailMessage->line("{$name}: {$value}");
});
return $mailMessage;
}