Adjust how deleted forums get shown

- In some cases deleted items weren't visible from the index view
- There also shouldn't be any reason why they can't be shown when searched for specifically
-- This also matches the behavior on comments

app/models/forum_post.rb

@@ -65,6 +65,10 @@ class ForumPost < ApplicationRecord
         q = q.joins(:topic).where("forum_topics.category_id = ?", params[:topic_category_id].to_i)
       end
 
+      unless params[:is_deleted].present?
+        q = q.active
+      end
+
       q.apply_default_order(params)
     end
   end

app/models/forum_topic.rb

@@ -80,6 +80,10 @@ class ForumTopic < ApplicationRecord
         q = q.apply_default_order(params)
       end
 
+      unless params[:is_deleted].present?
+        q = q.active
+      end
+
       q
     end
   end