Update app.py

app.py

@@ -133,7 +133,7 @@ async def find_solutions(requirements: ReqGroupingResponse):
                 cleaned = cleaned[7:]
             if cleaned.startswith('```'):
                 cleaned = cleaned[3:]
-            if cleaned.endswith('```
+            if cleaned.endswith('```'):
                 cleaned = cleaned[:-3]
             cleaned = cleaned.strip()