Fix hardlink test.

Author: darnuria

heed/src/env.rs

@@ -833,9 +833,8 @@ mod tests {
     #[test]
     fn open_env_with_named_path_hardlink_and_no_subdir() {
         let dir = tempfile::tempdir().unwrap();
-        let dir_symlink = tempfile::tempdir().unwrap();
         let env_name = dir.path().join("babar.mdb");
-        let hardlink_name = dir_symlink.path().join("babar.mdb.link");
+        let hardlink_name = dir.path().join("babar.mdb.link");
 
         let mut envbuilder = EnvOpenOptions::new();
         unsafe { envbuilder.flag(crate::Flag::NoSubDir) };
@@ -844,7 +843,7 @@ mod tests {
             .open(&env_name)
             .unwrap();
 
-        std::os::unix::fs::symlink(&dir.path(), &hardlink_name).unwrap();
+        std::fs::hard_link(&env_name, &hardlink_name).unwrap();
         let _env = envbuilder
             .map_size(10 * 1024 * 1024) // 10MB
             .open(&hardlink_name)