Update initialize.py

initialize.py

@@ -38,7 +38,7 @@ def define_components(document_store, api_key):
         token=Secret.from_token(api_key)
     )
     generator.warm_up()
-    return retreiver, prompt_builder, generator
+    return retriever, prompt_builder, generator
 
 def define_pipeline(retreiver, prompt_builder, generator):
     basic_rag_pipeline = Pipeline()