cargo: run rustfmt on the codebase

[lucab]

This applies a rustfmt pass on the whole project, in order to avoid
spurious reflows while working on unrelated changes.

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Sanity checks:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Are you doing the PR on the next branch?
• Have you created/updated the relevant documentation page(s)?
  • LB: Not applicable

[lucab]

/cc @Keats

[Keats]

Thanks for that but it will cause merge issues with #1391 which I'm planning to merge in next this week.

[lucab]

@Keats no worries. I was playing around the codebase to see how feasible it is to implement backlinks, and noticed a few spurious reflows. Can you maybe throw a cargo fmt pass on top of #1391, whenever you are done?

[Keats]

Interesting, backlinks is the feature I want to add after the i18n changes!

[lucab]

Nice. I am not yet there though, as I am slowly wading through the codebase and plumbing through primitives. I guess I can start opening PRs for those as soon as polished, though.