fix clearing of screenshot before running tests

tests/conftest.py

@@ -47,7 +47,7 @@ def reset_globals() -> Generator[None, None, None]:
     importlib.reload(globals)
 
 
-@pytest.fixture(scope='session')
+@pytest.fixture(scope='session', autouse=True)
 def remove_all_screenshots() -> None:
     for name in os.listdir(Screen.SCREENSHOT_DIR):
         os.remove(os.path.join(Screen.SCREENSHOT_DIR, name))