Python 3.8 syntax compatibility

src/incremental/tests/test_pyproject.py

@@ -15,7 +15,7 @@ class VerifyPyprojectDotTomlTests(TestCase):
     """Test the `_load_pyproject_toml` helper function"""
 
     def _loadToml(
-        self, toml: str, *, path: os.PathLike | None = None
+        self, toml: str, *, path: Optional[os.PathLike] = None
     ) -> Optional[_IncrementalConfig]:
         """
         Read a TOML snipped from a temporary file with `_load_pyproject_toml`