Fixed import typo (#11278)

Fixed small import typo in react_docstore documentation

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Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>

docs/extras/modules/agents/agent_types/react_docstore.ipynb

@@ -17,7 +17,8 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from langchain.llms import OpenAI\from langchain.utilities import Wikipedia\n",
+    "from langchain.llms import OpenAI\n",
+    "from langchain.docstore import Wikipedia\n",
     "from langchain.agents import initialize_agent, Tool\n",
     "from langchain.agents import AgentType\n",
     "from langchain.agents.react.base import DocstoreExplorer\n",