Add "add days" to current subscription logic

apps/school/templates/blocks/_schedule_purchased_item.html

@@ -16,7 +16,7 @@
       {% include './open_lesson.html' %}
       {% endif %}
       {% else %}
-      {% include './pay_btn.html' %}
+      {% include './day_pay_btn.html' %}
       {% endif %}
     </div>
     {% comment %}

apps/school/templates/blocks/day_pay_btn.html

@@ -0,0 +1,6 @@
+<a
+  {% if not user.is_authenticated %}
+  data-popup=".js-popup-auth"
+  {% endif %}
+  href="{% url 'school/checkout' %}?weekdays={{ school_schedule.weekday }}&add_days=true"
+>купить</a>