Remove unnecessary string literal concatenations (#30360)

tests/components/facebox/test_image_processing.py

@@ -81,7 +81,7 @@ VALID_CONFIG = {
 def mock_healthybox():
     """Mock fb.check_box_health."""
     check_box_health = (
-        "homeassistant.components.facebox.image_processing." "check_box_health"
+        "homeassistant.components.facebox.image_processing.check_box_health"
     )
     with patch(check_box_health, return_value=MOCK_BOX_ID) as _mock_healthybox:
         yield _mock_healthybox