title: wp_schedule_single_event never executes
body: <p>I have a problem that makes no sense to me.</p>
  <p>I striped the code down to minimum code but the cron job never fires.</p>
  <pre><code>
  function do_this_cron() {
      file_put_contents('/home/vagrant/Code/wordpress/test.log', &quot;schedule event run\n&quot;, FILE_APPEND);
  
  }
  add_action( 'my_new_event', 'do_this_cron' );
  
  $time = time() + MINUTE_IN_SECONDS * 2;
  $ret = wp_schedule_single_event($time, 'my_new_event');
  var_dump($ret) // always returns true
  </code></pre>
  <p>I have a cron manager plugin installed which lets me run the cron manually, but even there i can execute the job but it never runs the function.</p>
  <p>Anyone have any ideas why this is not running?</p>