Add avatar URL to Discourse Connect

Discourse should download and set the avatar if the user doesn't have
one set yet.

app/components/app_catalog/web_app_icon_component.rb

@@ -9,13 +9,5 @@ module AppCatalog
         @image_url = image_url_for(web_app.apple_touch_icon)
       end
     end
-
-    def image_url_for(attachment)
-      if Setting.s3_enabled?
-        s3_image_url(attachment)
-      else
-        Rails.application.routes.url_helpers.rails_blob_path(attachment, only_path: true)
-      end
-    end
   end
 end