[Bug]: IndentationError: unindent does not match any outer indentatio… (#1579)

### What problem does this PR solve?

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### Type of change

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

[Bug]: IndentationError: unindent does not match any outer indentation
level #1569

graph/component/duckduckgo.py

                 duck_res = [{"content": '<a href="' + i["url"] + '">' + i["title"] + '</a>    ' + i["body"]} for i in
                             ddgs.news(ans, max_results=self._param.top_n)]
 
-       if not duck_res:
-           return DuckDuckGo.be_output("")
+        if not duck_res:
+            return DuckDuckGo.be_output("")
 
         df = pd.DataFrame(duck_res)
         if DEBUG: print(df, ":::::::::::::::::::::::::::::::::")