fix: Fix schema linking error

examples/awel/simple_nl_schema_sql_chart_example.py

@@ -9,7 +9,7 @@
 from dbgpt.core.awel import DAG, HttpTrigger, JoinOperator, MapOperator
 from dbgpt.datasource.rdbms.base import RDBMSDatabase
 from dbgpt.datasource.rdbms.conn_sqlite import SQLiteTempConnect
-from dbgpt.model import OpenAILLMClient
+from dbgpt.model.proxy import OpenAILLMClient
 from dbgpt.rag.embedding.embedding_factory import DefaultEmbeddingFactory
 from dbgpt.rag.operators.schema_linking import SchemaLinkingOperator
 from dbgpt.storage.vector_store.chroma_store import ChromaVectorConfig