fix bug with finished stream, add finished stream to dummy producer

broker/src/asapo_broker/database/mongodb.go

broker/src/asapo_broker/database/mongodb_test.go

examples/consumer/getnext/getnext.cpp

...ples/producer/dummy-data-producer/dummy_data_producer.cpp

...automatic/full_chain/simple_chain_metadata/check_linux.sh

...omatic/full_chain/simple_chain_metadata/check_windows.bat