Move pagination_max_id and pagination_since_id into api/base controller (#28844)

app/controllers/api/v1/scheduled_statuses_controller.rb

@@ -63,11 +63,7 @@ class Api::V1::ScheduledStatusesController < Api::BaseController
     @statuses.size == limit_param(DEFAULT_STATUSES_LIMIT)
   end
 
-  def pagination_max_id
-    @statuses.last.id
-  end
-
-  def pagination_since_id
-    @statuses.first.id
+  def pagination_collection
+    @statuses
   end
 end