Remove placeholder tempest test

We don't really need this placeholder here now,
test_volume_unicode.CinderUnicodeTest is probably a
sufficient test for this role.

Change-Id: I9dd58c05d08b6bcf2d8880e7856f679f57b0849c

cinder/tests/tempest/api/volume/test_volume_placeholder.py

@@ -1,25 +0,0 @@
-# Copyright 2015
-# All Rights Reserved.
-#
-#    Licensed under the Apache License, Version 2.0 (the "License"); you may
-#    not use this file except in compliance with the License. You may obtain
-#    a copy of the License at
-#
-#         http://www.apache.org/licenses/LICENSE-2.0
-#
-#    Unless required by applicable law or agreed to in writing, software
-#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-#    License for the specific language governing permissions and limitations
-#    under the License.
-
-from tempest.tests import base
-
-
-class CinderPlaceholderTest(base.TestCase):
-    """Placeholder test for adding in-tree Cinder tempest tests."""
-    # TODO(smcginnis) Remove once real tests are added
-
-    def test_placeholder(self):
-        expected = 'This test is temporary and should be removed!'
-        self.assertEqual(expected, expected)