Add tests for serialize and deserialize witness set properties
requested to merge rm-test-serialize-and-deserialize-_witness_set_properties into bw_expose_witness_set_properties2python
Related: !174 (merged)
This is MR with tests for methods serialize_witness_set_properties and deserialize_witness_set_properties.
There were prepare tests positive tests and negative tests for calling method with missing, additional or incorrect arguments.