Fix top_p value bug in quickstart example in docs (#1110)

docs/get-started/quickstart.mdx

@@ -48,6 +48,7 @@ llm:
   provider: huggingface
   config:
     model: 'mistralai/Mistral-7B-v0.1'
+    top_p: 0.5
 embedder:
   provider: huggingface
   config: