Support debug components. (#3994)

### What problem does this PR solve?

#3993

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

api/apps/document_app.py

@@ -552,7 +552,7 @@ def parse():
         })
         driver = Chrome(options=options)
         driver.get(url)
-        res_headers = [r.response.headers for r in driver.requests]
+        res_headers = [r.response.headers for r in driver.requests if r and r.response]
         if len(res_headers) > 1:
             sections = RAGFlowHtmlParser().parser_txt(driver.page_source)
             driver.quit()