fix: training loss is a zero dimensional tensor

Should fix the problem with EarlyStopping callback.

examples/cli/gmlvq.py

@@ -1,12 +1,11 @@
 """GMLVQ example using the MNIST dataset."""
 
-import torch
-from pytorch_lightning.utilities.cli import LightningCLI
-
 import prototorch as pt
+import torch
 from prototorch.models import ImageGMLVQ
 from prototorch.models.abstract import PrototypeModel
 from prototorch.models.data import MNISTDataModule
+from pytorch_lightning.utilities.cli import LightningCLI
 
 
 class ExperimentClass(ImageGMLVQ):

examples/knn_iris.py

@@ -2,12 +2,11 @@
 
 import argparse
 
+import prototorch as pt
 import pytorch_lightning as pl
 import torch
 from sklearn.datasets import load_iris
 
-import prototorch as pt
-
 if __name__ == "__main__":
     # Command-line arguments
     parser = argparse.ArgumentParser()