Revert "chore: pinecone response to DocumentChunkWithScore (openai#395)"

This reverts commit b02139d.

datastore/providers/pinecone_datastore.py

@@ -159,7 +159,7 @@ async def _single_query(query: QueryWithEmbedding) -> QueryResult:
                 result = DocumentChunkWithScore(
                     id=result.id,
                     score=score,
-                    text=str(metadata["text"]) if metadata and "text" in metadata else "",
+                    text=metadata["text"] if metadata and "text" in metadata else None,
                     metadata=metadata_without_text,
                 )
                 query_results.append(result)