get last stream for receiver, update tests

CHANGELOG.md

broker/src/asapo_broker/database/mongodb_substreams.go

common/cpp/include/common/data_structs.h

common/cpp/src/data_structs/data_structs.cpp

common/cpp/src/database/mongodb_client.cpp

common/cpp/src/database/mongodb_client.h

common/cpp/unittests/data_structs/test_data_structs.cpp

producer/api/python/asapo_producer.pxd

producer/api/python/asapo_producer.pyx.in

...s/request_handler/test_request_handler_db_last_stream.cpp

...s/request_handler/test_request_handler_db_stream_info.cpp

tests/automatic/consumer/consumer_api/consumer_api.cpp

tests/automatic/consumer/consumer_api_python/consumer_api.py

tests/automatic/producer/python_api/check_linux.sh

tests/automatic/producer/python_api/check_windows.bat

tests/automatic/producer/python_api/producer_api.py