Fix the password reset form

Django crispy is bow using a filter rather than a tag.

Using the `crispy` tag resulted in two imbricated forms being
generated, and a broken "send" button.

la_chariotte/accounts/templates/registration/password_reset_form.html

@@ -8,7 +8,8 @@
     <div class="box">
         <form method="POST">
             <p>Entrez votre mail pour recevoir les instructions pour le réinitialiser.</p>
-            {% crispy form %}
+            {{ form | crispy }}
+            {% csrf_token %}
             <div class="buttons">
                 <input class="button is-primary" type="submit" value="Envoyer">
             </div>