Address clippy warnings

native/src/base/files.rs

@@ -1031,8 +1031,9 @@ pub fn parse_mount_info(pid: &str) -> Vec<MountInfo> {
     res
 }
 
-#[derive(Clone)]
+#[derive(Default, Clone)]
 pub enum SharedFd {
+    #[default]
     None,
     Shared(Arc<OwnedFd>),
 }
@@ -1058,9 +1059,3 @@ impl SharedFd {
         }
     }
 }
-
-impl Default for SharedFd {
-    fn default() -> Self {
-        SharedFd::None
-    }
-}