Kani

Add contracts for NonZero::from_mut_unchecked #1962

Job	Run time
Verify std library using autoharness (ubuntu-latest)	55m 4s
Verify std library using autoharness (macos-latest)	47m 28s
Verify std library (partition 3)	47m 22s
Verify std library (partition 2)	52m 2s
Verify std library (partition 4)	49m 29s
Verify std library (partition 1)	58m 16s
Verify std library (partition 3)	32m 53s
Verify std library (partition 2)	28m 13s
Kani Autoharness Analyzer	33m 40s
Kani Metrics (macos-latest)	43m 47s
Verify std library (partition 1)	45m 9s
Kani List	47m 6s
Kani Metrics (ubuntu-latest)	44m 8s
Verify std library (partition 4)	41m 39s
Build JSON from logs (macos-latest)	12s
Build JSON from logs (ubuntu-latest)	19s
	10h 26m 47s

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