fix DALI example
🐛 Bug
failing DALI example after upgrading to 0.28
self = <pl_examples.basic_examples.dali_image_classifier.DALIClassificationLoader object at 0x7f1180070b90> | 820s

| def __len__(self):
| batch_count = self._size // (self._num_gpus * self.batch_size)
| >       last_batch = 1 if self._fill_last_batch else 0
| E       AttributeError: 'DALIClassificationLoader' object has no attribute '_fill_last_batch'
| pl_examples/basic_examples/dali_image_classifier.py:104: AttributeError

To Reproduce

  
    
      pytorch-lightning/pl_examples/basic_examples/dali_image_classifier.py
    
    
        Lines 102 to 105
      in
      94a9d3d
    
  
  
    

        
          
           def __len__(self): 
        

        
          
               batch_count = self._size // (self._num_gpus * self.batch_size) 
        

        
          
               last_batch = 1 if self._fill_last_batch else 0 
        

        
          
               return batch_count + last_batch 
        
    
  


Additional context
it happened after v0.28 release
https://github.com/NVIDIA/DALI/releases/tag/v0.28.0