fix: remove incorrect GoogleSearchTool() `provider` arg

unit2/smolagents/multiagent_notebook.ipynb

@@ -5545,7 +5545,7 @@
         "web_agent = CodeAgent(\n",
         "    model=model,\n",
         "    tools=[\n",
-        "        GoogleSearchTool(provider=\"serper\"),\n",
+        "        GoogleSearchTool(),\n",
         "        VisitWebpageTool(),\n",
         "        calculate_cargo_travel_time,\n",
         "    ],\n",