llama_index: [Bug]: KnowledgeGraphQueryEngine fails with AttributeError

Bug Description

Both docs/examples/query_engine/knowledge_graph_query_engine.ipynb and docs/examples/query_engine/knowledge_graph_rag_query_engine.ipynb examples are failing due to following error: AttributeError: 'NoneType' object has no attribute 'kwargs' on KnowledgeGraphQueryEngine().query().

Version

llama-index==0.10.7

Steps to Reproduce

First occurrence:

1. Start running the notebook: docs/examples/query_engine/knowledge_graph_query_engine.ipynb
2. You will experience AttributeError: 'NoneType' object has no attribute 'kwargs' when running KnowledgeGraphQueryEngine().query() with llama-index==0.10.7.

Second occurrence:

1. Start running the notebook: docs/examples/query_engine/knowledge_graph_rag_query_engine.ipynb
2. You will experience WARNING:llama_index.core.indices.knowledge_graph.retrievers:Error in retrieving from nl2graphquery: 'NoneType' object has no attribute 'kwargs' when running query_engine_with_nl2graphquery.query() with llama-index==0.10.7.

Relevant Logs/Tracbacks

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In[28], line 1
----> 1 response = query_engine.query(
      2     "Tell me about Peter Quill?",
      3 )
      4 display(Markdown(f"<b>{response}</b>"))

File ~/Experimental/jupyter-ws/.venv/lib/python3.11/site-packages/llama_index/core/base/base_query_engine.py:40, in BaseQueryEngine.query(self, str_or_query_bundle)
     38 if isinstance(str_or_query_bundle, str):
     39     str_or_query_bundle = QueryBundle(str_or_query_bundle)
---> 40 return self._query(str_or_query_bundle)

File ~/Experimental/jupyter-ws/.venv/lib/python3.11/site-packages/llama_index/core/query_engine/knowledge_graph_query_engine.py:199, in KnowledgeGraphQueryEngine._query(self, query_bundle)
    195 """Query the graph store."""
    196 with self.callback_manager.event(
    197     CBEventType.QUERY, payload={EventPayload.QUERY_STR: query_bundle.query_str}
    198 ) as query_event:
--> 199     nodes: List[NodeWithScore] = self._retrieve(query_bundle)
    201     response = self._response_synthesizer.synthesize(
    202         query=query_bundle,
    203         nodes=nodes,
    204     )
    206     if self._verbose:

File ~/Experimental/jupyter-ws/.venv/lib/python3.11/site-packages/llama_index/core/query_engine/knowledge_graph_query_engine.py:154, in KnowledgeGraphQueryEngine._retrieve(self, query_bundle)
    152 def _retrieve(self, query_bundle: QueryBundle) -> List[NodeWithScore]:
    153     """Get nodes for response."""
--> 154     graph_store_query = self.generate_query(query_bundle.query_str)
    155     if self._verbose:
    156         print_text(f"Graph Store Query:\n{graph_store_query}\n", color="yellow")

File ~/Experimental/jupyter-ws/.venv/lib/python3.11/site-packages/llama_index/core/query_engine/knowledge_graph_query_engine.py:132, in KnowledgeGraphQueryEngine.generate_query(self, query_str)
    129 """Generate a Graph Store Query from a query bundle."""
    130 # Get the query engine query string
--> 132 graph_store_query: str = self._llm.predict(
    133     self._graph_query_synthesis_prompt,
    134     query_str=query_str,
    135     schema=self._graph_schema,
    136 )
    138 return graph_store_query

File ~/Experimental/jupyter-ws/.venv/lib/python3.11/site-packages/llama_index/core/llms/llm.py:249, in LLM.predict(self, prompt, **prompt_args)
    243 def predict(
    244     self,
    245     prompt: BasePromptTemplate,
    246     **prompt_args: Any,
    247 ) -> str:
    248     """Predict."""
--> 249     self._log_template_data(prompt, **prompt_args)
    251     if self.metadata.is_chat_model:
    252         messages = self._get_messages(prompt, **prompt_args)

File ~/Experimental/jupyter-ws/.venv/lib/python3.11/site-packages/llama_index/core/llms/llm.py:170, in LLM._log_template_data(self, prompt, **prompt_args)
    165 def _log_template_data(
    166     self, prompt: BasePromptTemplate, **prompt_args: Any
    167 ) -> None:
    168     template_vars = {
    169         k: v
--> 170         for k, v in ChainMap(prompt.kwargs, prompt_args).items()
    171         if k in prompt.template_vars
    172     }
    173     with self.callback_manager.event(
    174         CBEventType.TEMPLATING,
    175         payload={
   (...)
    180         },
    181     ):
    182         pass

AttributeError: 'NoneType' object has no attribute 'kwargs'