fix l1 loss usage

mu_map/training/distance.py

@@ -36,7 +36,7 @@ class Training(AbstractTraining):
 
     def _eval_batch(self, recons: torch.Tensor, mu_maps: torch.Tensor) -> float:
         mu_maps_predicted = self.model(recons)
-        loss = torch.nn.functional.loss.l1(mu_maps_predicted, mu_maps)
+        loss = torch.nn.functional.l1_loss(mu_maps_predicted, mu_maps)
         return loss.item()