refacgtor, add connection tag to monitoring

receiver/src/connection.cpp

receiver/src/connection.h

receiver/src/receiver.cpp

receiver/src/statistics.cpp

receiver/src/statistics.h

receiver/src/statistics_sender_influx_db.cpp

receiver/unittests/test_connection.cpp

receiver/unittests/test_statistics.cpp

receiver/unittests/test_statistics_sender_influx_db.cpp

tests/automatic/full_chain/simple_chain/CMakeLists.txt

tests/automatic/full_chain/simple_chain/check_linux.sh

...tomatic/producer_receiver/check_monitoring/CMakeLists.txt

...tomatic/producer_receiver/check_monitoring/check_linux.sh

...tic/producer_receiver/transfer_single_file/CMakeLists.txt

...tic/producer_receiver/transfer_single_file/check_linux.sh

tests/automatic/settings/receiver.json.tpl