fix usage of snapshot epoch param in training

mu_map/training/default.py

@@ -40,7 +40,7 @@ class Training():
             self.lr_scheduler.step()
             logger.debug(f"Update learning rate from {_previous:.4f} to {self.lr_scheduler.get_last_lr()[0]:.4f}")
 
-            if epoch % self.snapshot_epoch:
+            if epoch % self.snapshot_epoch == 0:
                 self.store_snapshot(epoch)
 
             logger.debug(f"Finished epoch {str(epoch):>{len(str(self.epochs))}}/{self.epochs + 1}")