test_du.rs ERROR: `cargo clippy`: this expression creates a reference which is immediately dereferenced by the compiler

[oech3]

[Prepare, build and test: tests/by-util/test_du.rs#L535](https://github.com/uutils/coreutils/commit/4fa689af89fea049895086905a1418b4ebc45049#annotation_51200054433)
ERROR: `cargo clippy`: this expression creates a reference which is immediately dereferenced by the compiler (file:'tests/by-util/test_du.rs', line:535)

https://github.com/uutils/coreutils/actions/runs/24330261736/job/71034389757