async def test_start_already_running(self):
        """Test starting the scheduler when it's already running."""
        scheduler = PlatformScheduler()
        scheduler.running = True

        # Mock methods
        scheduler.update_all_next_scheduled_runs = AsyncMock()

        await scheduler.start()

        # Assert update method not called again
        scheduler.update_all_next_scheduled_runs.assert_not_called()
Test starting the scheduler when it's already running.
backend/tests/unit/platform/test_scheduler.py