rustup-utils: Remove unused import

Trivial warning fix

Signed-off-by: Daniel Silverstone <[email protected]>

Author: kinnison

src/rustup-utils/src/utils.rs

@@ -9,7 +9,6 @@ use std::fs::{self, File};
 use std::io::{self, Write};
 use std::path::{Path, PathBuf};
 use std::process::Command;
-use std::sync::atomic::{AtomicBool, Ordering, ATOMIC_BOOL_INIT};
 use url::Url;
 
 #[cfg(windows)]