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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fix name of rule in example of `extend-per-file-ignores` in `options.rs`
file.
It was `E401` but in configuration example `E402` was listed. Just a
tiny mismatch.
## Test Plan
<!-- How was it tested? -->
Just by my eyes :).
6aefe71c56