v3 test utils, don't modify input parameter
v3 test utils, don't modify input parameter

As mentioned in https://review.openstack.org/#/c/61046/ for
test_update, we should not modify the input req_ref in test_create
instead we should make a copy

Change-Id: I649433596a3ebbf2133eb724f09eb4bd470b7cdd

varunarya10/keystonemiddleware