Update config.json

The label for livestock is displayed as "Tree." By changing the `label_dict` to "Livestock," we can set the default label to "Livestock."

config.json

@@ -4,7 +4,7 @@
   "existing_train_dataloader": null,
   "existing_val_dataloader": null,
   "label_dict": {
-    "Tree": 0
+    "Livestock": 0
   },
   "model": null,
   "num_classes": 1,