Remove previous broadcasts from the dashboard

Since they have their own page now they don’t need to also appear on the
dashboard.

app/main/views/broadcast.py

@@ -71,11 +71,6 @@ def get_broadcast_dashboard_partials(service_id):
             broadcasts=broadcast_messages.with_status('broadcasting'),
             empty_message='You do not have any live alerts at the moment',
         ),
-        previous_broadcasts=render_template(
-            'views/broadcast/partials/dashboard-table.html',
-            broadcasts=broadcast_messages.with_status('cancelled', 'completed'),
-            empty_message='You do not have any previous alerts',
-        ),
     )
 
 

app/templates/views/broadcast/dashboard.html

@@ -34,12 +34,4 @@
     'pending_approval_broadcasts'
   ) }}
 
-  <h2 class="heading-medium govuk-!-margin-bottom-2">Previous alerts</h2>
-
-  {{ ajax_block(
-    partials,
-    url_for('.broadcast_dashboard_updates', service_id=current_service.id),
-    'previous_broadcasts'
-  ) }}
-
 {% endblock %}