Periodic cleanup of emails does not exist in 2.0

Currently I have this in a cron job:

$now = new DrupalDateTime('-90 days');
$delete = \Drupal::database()->delete('mail_safety_dashboard');
$delete->condition('sent', $now->getTimestamp(), '<');
$delete->execute();

We could set this up in a container with dependency injection, and add a config to set the retention time.

Thank you laboratory.mike, your solution is a perfect stop gap until we get an actual settings page and this functionality incorporated into the module itself.

/**
 * Implements hook_mail().
 */
function mymodule_helper_cron() {
  // Delete old mail logs.
  $now = new DrupalDateTime('-90 days');
  $delete = \Drupal::database()->delete('mail_safety_dashboard');
  $delete->condition('sent', $now->getTimestamp(), '<');
  $delete->execute();
}