simplify enum chain of thought

Author: aaronvg

tutorials/baml_src/classification-guide/chain_of_thought.baml

@@ -1,13 +1,4 @@
 // https://docs.boundaryml.com/v3/guides/classification/level3
-class CategoryWithReasoning {
-  reasoning_steps string @description(#"
-    Some clues and reasoning steps to help the user
-    understand why the category was chosen.
-  "#)
-  category Category @alias(chosen_category) @description(#"
-    The category identifier or name.
-  "#)
-} 
 
 impl<llm, ClassifyMessage> version3 {
   client GPT4