Clippy treated Rust 2021 as Rust 2015, because 2018 was checked with `==` instead of `>=`. This fixes that, such that 2018-specific things are also enabled for 2021.
Clippy treated Rust 2021 as Rust 2015, because 2018 was checked with `==` instead of `>=`. This fixes that, such that 2018-specific things are also enabled for 2021.