Remove deprecated task in load_dataset
Author: albertvillanova
Pull request: yes

# What does this PR do?

Remove deprecated `task` in `load_dataset` from tensorflow example. This parameter was deprecated in datasets-2.14.0 one year ago:
- https://github.com/huggingface/datasets/pull/5865

Once datasets-3.0 is released, it will raise an error and transformers CI will break.

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Fixes #33432


## Before submitting
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- [ ] Did you write any new necessary tests?


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Comments:
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