fix regression

(cherry picked from commit 8c1f07c06e91ba79e2b9adf41f9b602e647dce3e)

document_qa/document_qa_engine.py

@@ -254,7 +254,7 @@ class DocumentQAEngine:
             hash = metadata[0]['hash']
 
         if hash not in self.embeddings_dict.keys() and (
-                'documents' in self.embeddings_dict.get() and len(self.embeddings_dict.get()['documents']) == 0):
+                'documents' in self.embeddings_dict[hash].get() and len(self.embeddings_dict[hash].get()['documents']) == 0):
             self.embeddings_dict[hash] = Chroma.from_texts(texts,
                                                            embedding=self.embedding_function,
                                                            metadatas=metadata,