Drop asynctest (#44746)

tests/components/vera/test_cover.py

@@ -1,12 +1,12 @@
 """Vera tests."""
+from unittest.mock import MagicMock
+
 import pyvera as pv
 
 from homeassistant.core import HomeAssistant
 
 from .common import ComponentFactory, new_simple_controller_config
 
-from tests.async_mock import MagicMock
-
 
 async def test_cover(
     hass: HomeAssistant, vera_component_factory: ComponentFactory