define build step for ease of use

Signed-off-by: Ryan Cook <[email protected]>

recipes/natural_language_processing/chatbot/README.md

@@ -98,6 +98,7 @@ The local Model Service relies on a volume mount to the localhost to access the
 
 ```bash
 # from path model_servers/llamacpp_python from repo containers/ai-lab-recipes
+make build
 make run
 ```