test(maas): use MaaSModelRef from wrapper

Author: SB159

tests/model_serving/model_server/maas_billing/maas_subscription/conftest.py

@@ -22,13 +22,12 @@
 from utilities.plugins.constant import OpenAIEnpoints
 from utilities.resources.maa_s_auth_policy import MaaSAuthPolicy
 from utilities.resources.maa_s_subscription import MaaSSubscription
-from utilities.resources.maas_model_ref import MaaSModelRef
+from ocp_resources.maas_model_ref import MaaSModelRef
 
 LOGGER = get_logger(name=__name__)
 
 CHAT_COMPLETIONS = OpenAIEnpoints.CHAT_COMPLETIONS
 
-
 @pytest.fixture(scope="class")
 def maas_inference_service_tinyllama_free(
     admin_client: DynamicClient,