Add serialization docs PR request note for conditional attributes

Author: bf4

docs/general/serializers.md

@@ -34,6 +34,8 @@ Serialization of the resource `title`
 | `attribute :title { 'A Different Title'}` | `{ title: 'A Different Title' } `
 | `attribute :title`<br>`def title 'A Different Title' end` | `{ title: 'A Different Title' }`
 
+[PR please for conditional attributes:)](https://github.com/rails-api/active_model_serializers/pull/1403)
+
 ### Associations
 
 #### ::has_one