fix typo

model.py

@@ -132,7 +132,7 @@ class qa_template:
             with gr.Column():
                 gr.Markdown(dedent(f"""
                     # video to QA
-                    A test implementation to use vectorstres and mini llms to create
+                    A test implementation to use vectorstores and mini llms to create
                     a question answer chatbot interface for _youtube videos_
                                    """))
                 chatbot = gr.Chatbot()