Add unexpected cfgs to `[lints]` table #2708

Job	Run time
semver	15s
Verify hyper.h is up to date	13s
Check Style	6s
features	41s
minimal-versions	25s
Test C API (FFI)	38s
Test with Miri	2m 5s
Check MSRV	20s
Test stable on ubuntu-latest	1m 8s
udeps	23s
Test stable on windows-latest	3m 36s
Test stable on macOS-latest	1m 18s
Test beta on ubuntu-latest	1m 14s
Test beta on windows-latest	1m 58s
Test beta on macOS-latest	1m 18s
Test nightly on ubuntu-latest	1m 13s
Test nightly on windows-latest	2m 23s
Test nightly on macOS-latest	1m 37s
Check exposed types	16s
Build docs	21s
CI is green	1s
	21m 29s

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