[ examples] fix loading jsonl with load dataset in run translation example
Author: mathiasesn
Pull request: yes

# What does this PR do?

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Fixes #26868 


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- text models: @ArthurZucker and @younesbelkada
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Comments:
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_26924). All of your documentation changes will be reflected on that endpoint.

> LGTM, this might need to be propagated to other examples? Also can you update the pr description to say what this fixes and the name of the PR with [ `examples`] fix blablalbla

Update name of the PR to: [ examples] fix loading jsonl with load dataset in run translation example.

Sorry for the delay!