fix/format: various code that's escaped the linter (#2667)

_Every once in a while I run clippy and the pre-commit checks on
everything b/c stuff seems to fall through the cracks._

- fix: various code that's escaped the linter
- format: various code that's escaped the formatter
- update: `chrono` because a test was using a method only available in
v0.4.23 _(I don't know why that didn't fail in CI)_


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