fix typo

app.py

@@ -12,7 +12,7 @@ See the 🤗 Space showing off how to combine various metrics:
     [MarioBarbeque/CombinedEvaluationMetrics🪲](https://huggingface.co/spaces/MarioBarbeque/CombinedEvaluationMetrics). This collected fix thereby circumnavigates the 
     original, longstanding issue found [here](https://github.com/huggingface/evaluate/issues/234). We look forward to fixing this in a PR soon.
 
-In the specific use case of the `F1Fixed` metric, one writes the following:\n
+In the specific use case of the `FixedF1` metric, one writes the following:\n
 
 ```python
 f1 = FixedF1(average=...)