refactor: sync with stdlib type stub change python/typeshed#14847

We are following the earlier signature, so it is no longer compatible
and pyright errors out on that. Fix by simply narrowing the `path`
argument's type.

Signed-off-by: WANG Xuerui <[email protected]>

Author: xen0n

ruyi/pluginhost/unsandboxed.py

@@ -148,7 +148,7 @@ def _load_stmt_helper(
     @staticmethod
     def source_to_code(
         data: "Buffer | str | ast.Module",
-        path: "Buffer | str | os.PathLike[str]" = "<string>",
+        path: "str | os.PathLike[str]" = "<string>",
     ) -> CodeType:
         mod_ast: ast.Module
         if isinstance(data, ast.Module):