refactor: Update queue_status endpoint response key name

The key name in the response of the queue_status endpoint has been updated from "prnding" to "pending" to fix a typo. This change ensures consistency and improves the readability of the returned data.

Llama/app.py

@@ -82,7 +82,7 @@ async def create_item(prompt: Prompt):
 
 @app.get("/queue-status/")
 async def queue_status():
-    return {"prnding": items_pending, "processed": items_processed, "queue": queue}
+    return {"pending": items_pending, "processed": items_processed, "queue": queue}
 
 @app.post("/prompt-result/")
 async def prompt_status(prompt_status: PromptResult):