Update app.py

app.py

@@ -17,7 +17,7 @@ def start_haystack():
         split_length=200,
         split_respect_sentence_boundary=True,
     )
-    summarizer = TransformersSummarizer(model_name_or_path="facebook/bart-large-cnn")
+    summarizer = TransformersSummarizer(model_name_or_path="google/bigbird-pegasus-large-arxiv")
     return document_store, summarizer, preprocessor