Fix warning message in ElectraForCausalLM
Author: pbelevich
Pull request: yes

# What does this PR do?

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Fixes warning message in ElectraForCausalLM


## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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      Pull Request section?
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- [ ] Did you write any new necessary tests?


## Who can review?

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Models:

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Comments:
_The documentation is not available anymore as the PR was closed or merged._