title: Django LogoutView does not emit user_logged_out signal
body: <p>I have an app that does not receive the <code>user_logged_out</code> signal that, in theory, should have been sent by <code>LogoutView</code>.</p>
  
  <p>urls.py:</p>
  
  <pre class="lang-py prettyprint-override"><code>...
     path('accounts/logout/',
        auth_views.LogoutView.as_view(template_name='registration/logout.html'),
           name='logout'),
  ...
  </code></pre>
  
  <p>myapp/signals.py</p>
  
  <pre class="lang-py prettyprint-override"><code>from django.contrib.auth import user_logged_out
  from django.dispatch import receiver
  
  
  @receiver(user_logged_out)
  def extra_logout(sender, request, user, **kwargs):
      # does some stuff
  </code></pre>
  
  <p>myapp/apps.py</p>
  
  <pre class="lang-py prettyprint-override"><code>from django.apps import AppConfig
  
  class MyappConfig(AppConfig):
      name = 'myapp'
  
      def ready(self):
          import myapp.signals
          return super().ready()
  </code></pre>
  
  <p>Note that <code>myapp</code> is loaded, everything else works. The django session is destroyed when calling <code>accounts/logout/</code>, but my receiver never gets the signal.</p>
  
  <p>What am I doing wrong?</p>
  
  <p>Django 2.2.3, Python 3.7.3 on mac.</p>