fix: ruff formatting

src/_cohere/doc_index.py

@@ -14,7 +14,6 @@
 from langchain_cohere import CohereEmbeddings
 from langchain_community.llms import Cohere
 from langchain_core.prompts import PromptTemplate
-from langchain_core.output_parsers import StrOutputParser
 from operator import itemgetter
 from utils.config import Config
 from utils.response_model import QueryResult