test(shim): fix CI formatting and cfg warnings

Author: immanuwell

crates/shim/src/cgroup.rs

@@ -350,12 +350,10 @@ pub fn update_resources(cgroup: &Cgroup, resources: &LinuxResources) -> Result<(
 
 #[cfg(test)]
 mod tests {
-    use std::error::Error as _;
-    use std::path::PathBuf;
+    use std::{error::Error as _, path::PathBuf};
 
     use cgroups_rs::{
-        fs::error::ErrorKind,
-        fs::{hierarchies, Cgroup},
+        fs::{error::ErrorKind, hierarchies, Cgroup},
         CgroupPid,
     };
 

crates/shim/src/error.rs

@@ -89,7 +89,7 @@ pub enum Error {
     Unimplemented(String),
 }
 
-#[cfg(test)]
+#[cfg(all(test, target_os = "linux"))]
 pub(crate) fn is_permission_error(err: &Error) -> bool {
     match err {
         Error::IoError { err, .. } => err.kind() == std::io::ErrorKind::PermissionDenied,