replace slippers with django-cotton

main reason: slippers cannot pass request via context inside its
components, making it annoying to use template takes that take request.
more reasons: not actively worked on, no named slots, having to define
components in components.yaml + new components do not get registered
without restarting server

games/templates/list_purchases.html

@@ -5,6 +5,6 @@
 {% endblock title %}
 {% block content %}
     <div class="2xl:max-w-screen-2xl md:max-w-screen-md sm:max-w-screen-sm self-center">
-        {% simple_table columns=data.columns rows=data.rows page_obj=page_obj elided_page_range=elided_page_range %}
+        <c-simple-table :columns=data.columns :rows=data.rows :page_obj=page_obj :elided_page_range=elided_page_range />
     </div>
 {% endblock content %}