[tests] Fix test-database initialisation

tests/conftest.py

@@ -98,4 +98,4 @@ def montgomery_datadir(tmp_path_factory, request) -> pathlib.Path:
     with zipfile.ZipFile(archive) as zf:
         zf.extractall(database_dir)
 
-    return database_dir / "MontgomerySet_Light"
+    return database_dir