deprecated_safe
deprecated_safe_2024
Create a lint group `deprecated_safe` that includes `deprecated_safe_2024`. Addresses https://github.com/rust-lang/rust/issues/124866#issuecomment-2142814375.
Addresses https://github.com/rust-lang/rust/pull/124636#issuecomment-2132119534. I think that the diff display regresses a little, because it's no longer showing the `+` to show where the `unsafe {}` is added. I think it's still fine.
It warns about usages of `std::env::{set_var, remove_var}` with an automatic fix wrapping the call in an `unsafe` block.