Tests should all use test HA

tests/components/test_introduction.py

@@ -6,15 +6,16 @@ Test introduction.
 """
 import unittest
 
-import homeassistant.core as ha
 from homeassistant.components import introduction
 
+from tests.common import get_test_home_assistant
+
 
 class TestIntroduction(unittest.TestCase):
     """ Test Introduction. """
 
     def setUp(self):
-        self.hass = ha.HomeAssistant()
+        self.hass = get_test_home_assistant()
 
     def tearDown(self):
         """ Stop down stuff we started. """