feat(timezone)!: improves how pace handles timezones #527

Job	Run time
Build docs (stable, macos-latest)	43s
Clippy (Future) (beta)	2m 20s
Build docs (stable, ubuntu-latest)	22s
Clippy (stable)	32s
Clippy (Future) (nightly)	2m 17s
Build docs (stable, windows-latest)	1m 2s
Rustfmt	8s
ubuntu / stable / features	2m 24s
Check MSRV (pace-rs, 1.74.1)	2m 31s
Check MSRV (pace_core, 1.74.1)	1m 52s
Test (stable, macos-latest)	5m 44s
Check MSRV (pace_cli, 1.74.1)	1m 57s
Test (stable, ubuntu-latest)	2m 17s
Test (stable, windows-latest)	4m 51s
Test (beta, macos-latest)	3m 35s
Test (beta, ubuntu-latest)	2m 1s
Test (beta, windows-latest)	3m 32s
Result (CI)	1s
	38m 9s

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