Wrong output on chapter4/fine-tuning

[DavidFM43]

Hi👋,
I think the output should be:

DatasetDict({
    train: Dataset({
        features: ['genre', 'input_values', 'attention_mask'],
        num_rows: 899
    })
    test: Dataset({
        features: ['genre', 'input_values', 'attention_mask'],
        num_rows: 100
    })
})

Instead of

audio-transformers-course/chapters/en/chapter4/fine-tuning.mdx

Lines 321 to 336 in c3a8701

	gtzan_encoded
	```
	**Output:**
	```out
	DatasetDict({
	train: Dataset({
	features: ['genre', 'input_values'],
	num_rows: 899
	})
	test: Dataset({
	features: ['genre', 'input_values'],
	num_rows: 100
	})
	})
	```

Since return_attention_mask=True in the feature_extractor. Is this the case?

[MHRDYN7]

@DavidFM43 you're right. Perhaps you could directly open a PR. In case you do not open a PR for this particular issue, I'll be opening one for this file and will make sure to include this change along with the other code changes.