Fix mypy

tests/test_cli.py

@@ -256,7 +256,7 @@ PROJECT_URL = "http://localhost:5000/project"
 
 
 @pytest.fixture
-def project_notebook(tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch):
+def project_notebook(tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch) -> None:
     cwd_path = tmp_path / "cwd"
     cwd_path.mkdir()
     monkeypatch.chdir(cwd_path)
@@ -346,7 +346,7 @@ def test_project_invalid_zip(
     tmp_path: pathlib.Path,
     time_machine: TimeMachineFixture,
     golden_special: GoldenTestFixture,
-):
+) -> None:
     time_machine.move_to(FROZEN_TIME)
     project_path = tmp_path / "project.zip"
     project_path.touch()