Test are broken on Tarantool 1.6

[rtsisyk]

test/lib/tarantool-python$ ./setup.py test
Traceback (most recent call last):
  File "/data/work/tarantool/master/test/lib/tarantool-python/tests/suites/test_dml.py", line 119, in test_07_call
    self.assertEqual(self.con.call('box.cjson.decode', '[123, 234, 345]'), [(123, 234, 345)])
  File "/data/work/tarantool/master/test/lib/tarantool-python/tarantool/connection.py", line 275, in call
    response = self._send_request(request)
  File "/data/work/tarantool/master/test/lib/tarantool-python/tarantool/connection.py", line 250, in _send_request
    request)
  File "/data/work/tarantool/master/test/lib/tarantool-python/tarantool/connection.py", line 182, in _send_request_wo_reconnect
    response = Response(self, self._read_response())
  File "/data/work/tarantool/master/test/lib/tarantool-python/tarantool/response.py", line 67, in __init__
    raise DatabaseError(self._return_code, self._return_message)
DatabaseError: (8450, "Procedure 'box.cjson.decode' is not defined")

[bigbes]

Fixed in latest master