feat(lib): missing Timer will warn or panic #2295

Job	Run time
Verify hyper.h is up to date	38s
Check Style	7s
features	19s
Test with Miri	1m 9s
udeps	29s
Test C API (FFI)	45s
Check MSRV	52s
Test stable on ubuntu-latest	1m 48s
Test stable on windows-latest	3m 47s
Test stable on macOS-latest	1m 39s
Test beta on ubuntu-latest	1m 18s
Test beta on windows-latest	1m 56s
Test beta on macOS-latest	1m 42s
Test nightly on ubuntu-latest	2m 2s
Test nightly on windows-latest	2m 36s
Test nightly on macOS-latest	1m 44s
Check exposed types	25s
Build docs	14s
CI is green	3s
	23m 33s

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