WIP: feat: `aggregate-timings-from-log` subcmd. #368

Job	Run time
Rustfmt (stable)	11s
cargo-deny	23s
block-autosquash-commits	0s
Check (ubuntu-latest, stable)	37s
Check (ubuntu-latest, beta)	36s
Check (windows-latest, stable)	2m 13s
Check (windows-latest, beta)	1m 55s
Check (macOS-latest, stable)	37s
Check (macOS-latest, beta)	40s
Clippy (stable)	40s
Documentation (stable)	38s
Clippy (beta)	38s
Test Suite (ubuntu-latest, stable)	59s
Documentation (beta)	33s
Test Suite (ubuntu-latest, beta)	5m 15s
Test Suite (windows-latest, stable)	2m 15s
Test Suite (windows-latest, beta)	2m 17s
Test Suite (macOS-latest, stable)	1m 0s
Test Suite (macOS-latest, beta)	1m 1s
	22m 28s

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