Fix verify_checks_output.
Fix verify_checks_output.

This was accidentally broken in
https://github.com/rust-lang/cargo/commit/cc5e9df64a7ed6b3657e9dd790e2e34387d33df5
causing it to not check in the error case (which is the only case that mattered).

rust-lang/cargo,rust-lang/cargo,rustyhorde/cargo,eminence/cargo,nipunn1313/cargo,nipunn1313/cargo,nipunn1313/cargo,nipunn1313/cargo,rustyhorde/cargo,rustyhorde/cargo,eminence/cargo,rust-lang/cargo,rustyhorde/cargo,rust-lang/cargo,eminence/cargo,eminence/cargo