Remove property overwrite attempt

Can't overwrite property ref https://github.com/Lightning-AI/lightning/blob/2.0.2/src/lightning/pytorch/trainer/trainer.py#L1384

So replaced with just an early return None ref https://github.com/Lightning-AI/lightning/blob/2.0.2/src/lightning/pytorch/core/hooks.py#L48-L49

multimodal/src/autogluon/multimodal/optimization/lit_module.py

@@ -239,13 +239,13 @@ def training_step(self, batch, batch_idx):
 
     def on_validation_start(self) -> None:
         if self.skip_final_val and self.trainer.should_stop:
-            self.trainer.val_dataloaders = []  # skip the final validation by setting val_dataloaders empty
             self.log(
                 self.validation_metric_name,
                 self.validation_metric,
                 on_step=False,
                 on_epoch=True,
             )
+            return None
         return super().on_validation_start()
 
     def validation_step(self, batch, batch_idx):