Delete duplicate if judgment

create_user() function has done if judgment, we don't need to
repeat it. This patch delete it for the code clean.

Change-Id: I3dbe99b31ffb4d971d2ca7b4be21941f6f30d3cb
diff --git a/tempest/api/compute/admin/test_quotas.py b/tempest/api/compute/admin/test_quotas.py
index b1f0755..7d97ce2 100644
--- a/tempest/api/compute/admin/test_quotas.py
+++ b/tempest/api/compute/admin/test_quotas.py
@@ -117,8 +117,6 @@
                                                password=password,
                                                project=project,
                                                email=email)
-        if 'user' in user:
-            user = user['user']
         user_id = user['id']
         self.addCleanup(self.identity_utils.delete_user, user_id)