make clippy happy (#6930)

Author: mattsse

crates/test-utils/src/fd_lock.rs

@@ -13,7 +13,7 @@ pub fn new_lock(lock_path: impl AsRef<Path>) -> RwLock<File> {
     fn new_lock(lock_path: &Path) -> RwLock<File> {
         let lock_file = pretty_err(
             lock_path,
-            OpenOptions::new().read(true).write(true).create(true).open(lock_path),
+            OpenOptions::new().read(true).write(true).create(true).truncate(false).open(lock_path),
         );
         RwLock::new(lock_file)
     }