Remove the get_hiera_key function

It is no longer used in tripleoclient.

Change-Id: I8e4347fc340b01efae9afefa8ddae3c8667774ad

tripleoclient/tests/test_utils.py

@@ -259,17 +259,6 @@ class TestWaitForStackUtil(TestCase):
 
         self.assertEqual(uuids, ['IJKLMNOP', ])
 
-    @mock.patch("subprocess.Popen")
-    def test_get_hiera_key(self, mock_popen):
-
-        process_mock = mock.Mock()
-        process_mock.communicate.return_value = ["pa$$word", ""]
-        mock_popen.return_value = process_mock
-
-        value = utils.get_hiera_key('password_name')
-
-        self.assertEqual(value, "pa$$word")
-
     @mock.patch("six.moves.configparser")
     @mock.patch("os.path.exists")
     def test_get_config_value(self, mock_path_exists, mock_config_parser):

tripleoclient/utils.py

@@ -449,19 +449,6 @@ def set_nodes_state(baremetal_client, nodes, transition, target_state,
         yield node.uuid
 
 
-def get_hiera_key(key_name):
-    """Retrieve a key from the hiera store
-
-    :param password_name: Name of the key to retrieve
-    :type  password_name: type
-
-    """
-    command = ["hiera", key_name]
-    p = subprocess.Popen(command, stdout=subprocess.PIPE)
-    out, err = p.communicate()
-    return out
-
-
 def get_config_value(section, option):
     # TODO(beagles): get_config_value is an odd name for this function as the
     # hard coding of undercloud-passwords makes this a