Skip negative tests of v3 server metadata

If sending long metadata to "create a server" API of Nova v3 API,
the API returns an OverLimit response now.

However the commit Ic17d2227909c9180ca86c9d578dad4c73ec57dfc will
change the response to BadRequest. To verify the commit on Jenkins,
it is necessary to skip the tests related to long metadata temporary.

Change-Id: Ic03c2247505780fbeda68e908298a98862ea0c7c
Related-Bug: #1273948
diff --git a/tempest/api/compute/v3/servers/test_server_metadata_negative.py b/tempest/api/compute/v3/servers/test_server_metadata_negative.py
index 4062696..5504b13 100644
--- a/tempest/api/compute/v3/servers/test_server_metadata_negative.py
+++ b/tempest/api/compute/v3/servers/test_server_metadata_negative.py
@@ -34,6 +34,7 @@
 
         cls.server_id = server['id']
 
+    @test.skip_because(bug="1273948")
     @test.attr(type=['gate', 'negative'])
     def test_server_create_metadata_key_too_long(self):
         # Attempt to start a server with a meta-data key that is > 255
@@ -43,7 +44,7 @@
         for sz in [256, 257, 511, 1023]:
             key = "k" * sz
             meta = {key: 'data1'}
-            self.assertRaises(exceptions.OverLimit,
+            self.assertRaises(exceptions.BadRequest,
                               self.create_test_server,
                               meta=meta)
 
diff --git a/tempest/api/compute/v3/servers/test_servers_negative.py b/tempest/api/compute/v3/servers/test_servers_negative.py
index e58d33d..675c4f8 100644
--- a/tempest/api/compute/v3/servers/test_servers_negative.py
+++ b/tempest/api/compute/v3/servers/test_servers_negative.py
@@ -191,12 +191,13 @@
                           self.create_test_server,
                           key_name=key_name)
 
+    @test.skip_because(bug="1273948")
     @test.attr(type=['negative', 'gate'])
     def test_create_server_metadata_exceeds_length_limit(self):
         # Pass really long metadata while creating a server
 
         metadata = {'a': 'b' * 260}
-        self.assertRaises(exceptions.OverLimit,
+        self.assertRaises(exceptions.BadRequest,
                           self.create_test_server,
                           meta=metadata)