Implement round-ties-to-even for Duration Debug for consistency with f64
## Summary
This PR proposes a fix for rust-lang/rust#103747 implementing IEEE-754 S4.3 roundTiesToEven for Duration Debug implementation.
## Testing
Added new test in `time.rs` for validating roundTiesToEven behavior in Duration formatting. Reran all debug formatting tests in `time.rs` with `./x test library/coretests --test-args time::debug_formatting`.
Jonathan Brouwer
2c0daa2301