bugfix: ensure the google_assistant component respects allow_unlock (#18874)

The `Config` object specific to the `google_assistant` component
had a default value for `allow_unlock`. We were not overriding this
default when constructing the Config object during `google_assistant`
component setup, whereas we do when setting up the `cloud` component.

To fix, we thread the `allow_unlock` parameter down through http setup,
and ensure that it's set correctly. Moreover, we also change the
ordering of the `Config` parameters, and remove the default. Future
refactoring should not miss it, as it is now a required parameter.

tests/components/google_assistant/test_trait.py

@@ -25,6 +25,7 @@ from tests.common import async_mock_service
 
 BASIC_CONFIG = helpers.Config(
     should_expose=lambda state: True,
+    allow_unlock=False,
     agent_user_id='test-agent',
 )