skip cfn_init test, it is failing too much

And there is no current progress on the bug.

Change-Id: I2604805d06a87973b8c30e56457fcd3648a666f4
Related-Bug: #1374175
diff --git a/tempest/scenario/orchestration/test_server_cfn_init.py b/tempest/scenario/orchestration/test_server_cfn_init.py
index 0ab4311..abda1f8 100644
--- a/tempest/scenario/orchestration/test_server_cfn_init.py
+++ b/tempest/scenario/orchestration/test_server_cfn_init.py
@@ -24,6 +24,7 @@
 
 class CfnInitScenarioTest(manager.OrchestrationScenarioTest):
 
+    @test.skip_because(bug="1374175")
     def setUp(self):
         super(CfnInitScenarioTest, self).setUp()
         if not CONF.orchestration.image_ref: