Fix credential creation

openstacksdk's Credential expects user_id and project_id, not user and
project. Previously, we would send payloads like

   {'type': 'ec2', 'blob': '{"access": "s3-user1", "secret": "s3-secret1"}'}

which Keystone would reject with

   'user_id' is a required property

Change-Id: I0544bef7df9247395f0726ea075112d6ac992252

openstackclient/identity/v3/credential.py

@@ -88,10 +88,10 @@ class CreateCredential(command.ShowOne):
         else:
             project = None
         credential = identity_client.create_credential(
-            user=user_id,
+            user_id=user_id,
             type=parsed_args.type,
             blob=parsed_args.data,
-            project=project,
+            project_id=project,
         )
 
         return _format_credential(credential)

openstackclient/tests/unit/identity/v3/test_credential.py

@@ -73,10 +73,10 @@ class TestCredentialCreate(identity_fakes.TestIdentityv3):
         columns, data = self.cmd.take_action(parsed_args)
 
         kwargs = {
-            'user': self.credential.user_id,
+            'user_id': self.credential.user_id,
             'type': self.credential.type,
             'blob': self.credential.blob,
-            'project': None,
+            'project_id': None,
         }
         self.identity_sdk_client.create_credential.assert_called_once_with(
             **kwargs
@@ -105,10 +105,10 @@ class TestCredentialCreate(identity_fakes.TestIdentityv3):
         columns, data = self.cmd.take_action(parsed_args)
 
         kwargs = {
-            'user': self.credential.user_id,
+            'user_id': self.credential.user_id,
             'type': self.credential.type,
             'blob': self.credential.blob,
-            'project': self.credential.project_id,
+            'project_id': self.credential.project_id,
         }
         self.identity_sdk_client.create_credential.assert_called_once_with(
             **kwargs