chore: split importing into two.

Author: Sol-Ell

src/bootstrap/src/core/build_steps/perf.rs

@@ -1,4 +1,5 @@
-use std::{env::consts::EXE_EXTENSION, fmt::{Display, Formatter}};
+use std::env::consts::EXE_EXTENSION;
+use std::fmt::{Display, Formatter};
 
 use crate::core::build_steps::compile::{Std, Sysroot};
 use crate::core::build_steps::tool::{RustcPerf, Rustdoc};