fix: remove `SubtestOutcome::Crash` #657

Job	Run time
Format TOML with Taplo	3s
Format Rust with `cargo fmt` (stable)	7s
Check (ubuntu-latest, beta)	36s
Check (macOS-latest, stable)	33s
Check (ubuntu-latest, stable)	37s
Check (windows-latest, beta)	1m 28s
Check (windows-latest, stable)	1m 29s
Check (macOS-latest, beta)	35s
cargo-deny	21s
block-autosquash-commits	-1s
Documentation (stable)	36s
Documentation (beta)	34s
Clippy (beta)	36s
Test Suite (ubuntu-latest, beta)	59s
Test Suite (windows-latest, stable)	2m 25s
Test Suite (windows-latest, beta)	2m 1s
Test Suite (macOS-latest, stable)	51s
Clippy (stable)	33s
Test Suite (macOS-latest, beta)	1m 6s
Test Suite (ubuntu-latest, stable)	1m 1s
	16m 30s

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