Add correct path from data-dir (#14894)

Fix issue in #14879 with incorrect subdirectory.
Before: Appended `vendor/autoload`
After: Appends `nushell/vendor/autoload`

crates/nu-protocol/src/eval_const.rs

@@ -321,7 +321,7 @@ pub fn get_vendor_autoload_dirs(_engine_state: &EngineState) -> Vec<PathBuf> {
     }
 
     if let Some(data_dir) = nu_path::data_dir() {
-        append_fn(PathBuf::from(data_dir).join("vendor").join("autoload"));
+        append_fn(into_autoload_path_fn(PathBuf::from(data_dir)));
     }
 
     if let Some(path) = std::env::var_os("NU_VENDOR_AUTOLOAD_DIR") {