Fix typo ; Update output.mdx (#23227)

docs/source/en/main_classes/output.mdx

@@ -31,7 +31,7 @@ outputs = model(**inputs, labels=labels)
 ```
 
 The `outputs` object is a [`~modeling_outputs.SequenceClassifierOutput`], as we can see in the
-documentation of that class below, it means it has an optional `loss`, a `logits` an optional `hidden_states` and
+documentation of that class below, it means it has an optional `loss`, a `logits`, an optional `hidden_states` and
 an optional `attentions` attribute. Here we have the `loss` since we passed along `labels`, but we don't have
 `hidden_states` and `attentions` because we didn't pass `output_hidden_states=True` or
 `output_attentions=True`.