Classification Tutorial: Replaced .dict() with .model_dump() method (#29701)

The .dict() method is deprecated inf Pydantic V2.0 and use `model_dump`
method instead.

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docs/docs/tutorials/classification.ipynb

@@ -154,7 +154,7 @@
    "id": "ff3cf30d",
    "metadata": {},
    "source": [
-    "If we want dictionary output, we can just call `.dict()`"
+    "If we want dictionary output, we can just call `.model_dump()`"
    ]
   },
   {
@@ -179,7 +179,7 @@
     "prompt = tagging_prompt.invoke({\"input\": inp})\n",
     "response = llm.invoke(prompt)\n",
     "\n",
-    "response.dict()"
+    "response.model_dump()"
    ]
   },
   {