fix typo in requirements.txt

[dsa]

Checklist

• [x] Read CONTRIBUTING.md, and accept the CLA by including the provided snippet. We will not accept PR without this.
• [ ] Run pre-commit hook.
• [ ] If you changed Rust code, run cargo check, cargo clippy, cargo test.

PR Description

[dsa]

I, dsa, confirm that I have read and understood the terms of the CLA of Kyutai-labs, as outlined in the repository's CONTRIBUTING.md, and I agree to be bound by these terms.

[LaurentMazare]

Thanks Russ!