Update json module to jsonutils

oslo project provide jsonutils, and we use it in many place[1],
this PS to update the remained json moudule to oslo jsonutils for
consistency.

[1]: 9594233ffd/tempest/lib/services/volume/v1/quotas_client.py (L15)

Change-Id: Ib8d9f49a1fdfa0f5e0cfb05a193dffb83e4cfe69

tempest/api/compute/servers/test_device_tagging.py

@@ -12,9 +12,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import json
-
 from oslo_log import log as logging
+from oslo_serialization import jsonutils as json
 
 from tempest.api.compute import base
 from tempest.common import utils

tempest/cmd/subunit_describe_calls.py

@@ -78,11 +78,11 @@ Output file JSON structure
 import argparse
 import collections
 import io
-import json
 import os
 import re
 import sys
 
+from oslo_serialization import jsonutils as json
 import subunit
 import testtools
 

tempest/scenario/test_server_basic_ops.py

@@ -13,7 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import json
+from oslo_serialization import jsonutils as json
 
 from tempest.common import utils
 from tempest.common import waiters

tempest/scenario/test_volume_boot_pattern.py

@@ -11,7 +11,7 @@
 #    under the License.
 
 from oslo_log import log as logging
-from oslo_serialization import jsonutils
+from oslo_serialization import jsonutils as json
 import testtools
 
 from tempest.common import utils
@@ -265,7 +265,7 @@ class TestVolumeBootPattern(manager.EncryptionScenarioTest):
         bdms = image.get('block_device_mapping')
         if not bdms:
             bdms = image['properties']['block_device_mapping']
-        bdms = jsonutils.loads(bdms)
+        bdms = json.loads(bdms)
         snapshot_id = bdms[0]['snapshot_id']
         self._delete_snapshot(snapshot_id)
 

tempest/tests/lib/common/test_rest_client.py

@@ -13,10 +13,10 @@
 #    under the License.
 
 import copy
-import json
 
 import fixtures
 import jsonschema
+from oslo_serialization import jsonutils as json
 import six
 
 from tempest.lib.common import http

tempest/tests/lib/services/identity/v2/test_token_client.py

@@ -12,9 +12,8 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import json
-
 import mock
+from oslo_serialization import jsonutils as json
 
 from tempest.lib.common import rest_client
 from tempest.lib import exceptions

tempest/tests/lib/services/identity/v3/test_token_client.py

@@ -12,9 +12,8 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import json
-
 import mock
+from oslo_serialization import jsonutils as json
 
 from tempest.lib.common import rest_client
 from tempest.lib import exceptions