chore: Only backup when passing --verify #2917

Job	Run time
semver	18s
Check Style	11s
Verify hyper.h is up to date	17s
features	42s
Test stable on ubuntu-latest	1m 12s
Test stable on windows-latest	2m 7s
Test stable on macOS-latest	1m 7s
Test cargo-c support (FFI)	21s
minimal-versions	29s
Test beta on ubuntu-latest	1m 9s
Test C API (FFI)	19s
Test beta on windows-latest	1m 53s
Test with Miri	2m 29s
Check MSRV	28s
Test beta on macOS-latest	1m 23s
udeps	19s
Test nightly on ubuntu-latest	1m 8s
Test nightly on windows-latest	2m 16s
Test nightly on macOS-latest	1m 17s
Build docs	14s
Check exposed types	16s
CI is green	1s
	19m 56s

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