Update unicode-width to 0.2.0

[printfn]

I updated the unicode-width dependency to 0.2.0. See the changelog here. None of the changes seem to affect rustc.

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @Mark-Simulacrum (or someone else) some time within the next two weeks.

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[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

[bors]

☔ The latest upstream changes (presumably #131098) made this pull request unmergeable. Please resolve the merge conflicts.