uucore: locale: Fix clippy warning

[drinkcat]

Looks like there is a CI coverage gap...

cargo +stable clippy --workspace --all-targets --all-features -- -D warnings

error: variables can be used directly in the `format!` string
   --> src/uucore/src/lib/mods/locale.rs:750:17
    |
750 |                 eprintln!("Init localization failed: {}", e);
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
    = note: `-D clippy::uninlined-format-args` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::uninlined_format_args)]`
help: change this to
    |
750 -                 eprintln!("Init localization failed: {}", e);
750 +                 eprintln!("Init localization failed: {e}");
    |

error: could not compile `uucore` (lib test) due to 1 previous error
warning: build failed, waiting for other jobs to finish...

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/misc/tee (passes in this run but fails in the 'main' branch)