Update tool_calling.ipynb (#26699)

There is a small bug in "TypedDict class" sample source.

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docs/docs/how_to/tool_calling.ipynb

@@ -179,7 +179,7 @@
     "    b: Annotated[int, ..., \"Second integer\"]\n",
     "\n",
     "\n",
-    "class multiply(BaseModel):\n",
+    "class multiply(TypedDict):\n",
     "    \"\"\"Multiply two integers.\"\"\"\n",
     "\n",
     "    a: Annotated[int, ..., \"First integer\"]\n",