BUG: Use custom checkpoint for test stage in DeepMIL (#318)

hi-ml-histopathology/src/histopathology/configs/classification/BaseMIL.py

@@ -216,7 +216,7 @@ def get_dataloader_kwargs(self) -> dict:
     def get_callbacks(self) -> List[Callback]:
         return super().get_callbacks() + [self.callbacks]
 
-    def get_path_to_best_checkpoint(self) -> Path:
+    def get_checkpoint_to_test(self) -> Path:
         """
         Returns the full path to a checkpoint file that was found to be best during training, whatever criterion
         was applied there. This is necessary since for some models the checkpoint is in a subfolder of the checkpoint