Many warnings on the CI pulled by non-tier1 target

[oech3]

https://github.com/uutils/coreutils/actions/runs/20693801647/job/59406110122#step:13:227

We should mask them. @ognevny

[ognevny]

it's possible to configure unexpected-cfgs lint so target_os = "cygwin" will be accepted too. I remembered that one of "support Cygwin" change by @Berrysoft added this workaround, but I don't remember where exactly... maybe he'll help

[cakebaker]

Probably in Cargo.toml, we already have an entry there for fuzzing.

[oech3]

Thankyou