uses skip_because where appropriate instead of regular skip

Change-Id: If37582fa6b4ea9ec36bf446de305a97ea525b1f9
diff --git a/tempest/cli/simple_read_only/test_nova.py b/tempest/cli/simple_read_only/test_nova.py
index 94415f0..1aa8f2c 100644
--- a/tempest/cli/simple_read_only/test_nova.py
+++ b/tempest/cli/simple_read_only/test_nova.py
@@ -22,6 +22,7 @@
 
 import tempest.cli
 from tempest.openstack.common import log as logging
+import tempest.test
 
 CONF = cfg.CONF
 
@@ -73,7 +74,7 @@
     def test_admin_dns_domains(self):
         self.nova('dns-domains')
 
-    @testtools.skip("Test needs parameters, Bug #1157349")
+    @tempest.test.skip_because(bug="1157349")
     def test_admin_dns_list(self):
         self.nova('dns-list')
 
@@ -111,7 +112,7 @@
     def test_admin_image_list(self):
         self.nova('image-list')
 
-    @testtools.skip("Test needs parameters, Bug #1157349")
+    @tempest.test.skip_because(bug="1157349")
     def test_admin_interface_list(self):
         self.nova('interface-list')
 
@@ -136,7 +137,7 @@
     def test_admin_secgroup_list(self):
         self.nova('secgroup-list')
 
-    @testtools.skip("Test needs parameters, Bug #1157349")
+    @tempest.test.skip_because(bug="1157349")
     def test_admin_secgroup_list_rules(self):
         self.nova('secgroup-list-rules')
 
diff --git a/tempest/scenario/test_stamp_pattern.py b/tempest/scenario/test_stamp_pattern.py
index 4f49d65..6812d64 100644
--- a/tempest/scenario/test_stamp_pattern.py
+++ b/tempest/scenario/test_stamp_pattern.py
@@ -18,7 +18,6 @@
 import time
 
 from cinderclient import exceptions as cinder_exceptions
-import testtools
 
 from tempest.common.utils.data_utils import rand_name
 from tempest import exceptions
@@ -142,7 +141,7 @@
         got_timestamp = ssh_client.exec_command('sudo cat /mnt/timestamp')
         self.assertEqual(self.timestamp, got_timestamp)
 
-    @testtools.skip("Skipped until the Bug #1205344 is resolved.")
+    @tempest.test.skip_because(bug="1205344")
     @tempest.test.services('compute', 'network', 'volume', 'image')
     def test_stamp_pattern(self):
         # prepare for booting a instance