fix: Removed a wrong key-word argument in `sigmoid_focal_loss()` function call (#31951)

Removed a wrong key-word argument in sigmoid_focal_loss() function call.

src/transformers/models/rt_detr/modeling_rt_detr.py

@@ -2163,7 +2163,7 @@ class RTDetrLoss(nn.Module):
         target_classes[idx] = target_classes_original
 
         target = F.one_hot(target_classes, num_classes=self.num_classes + 1)[..., :-1]
-        loss = sigmoid_focal_loss(src_logits, target, self.alpha, self.gamma, reduction="none")
+        loss = sigmoid_focal_loss(src_logits, target, self.alpha, self.gamma)
         loss = loss.mean(1).sum() * src_logits.shape[1] / num_boxes
         return {"loss_focal": loss}