Update data_collator.py
Author: neeravkaushal
Pull request: yes

Fix 10% random token replacement.

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Fixes # (issue)


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Models:

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Library:

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Comments:
Ah, got it! Thank you!

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_21629). All of your documentation changes will be reflected on that endpoint.