fix memleaks and race conditions

common/cpp/src/system_io/system_io.cpp

receiver/src/main.cpp

receiver/src/monitoring/receiver_monitoring_client.h

receiver/src/monitoring/receiver_monitoring_client_impl.cpp

receiver/src/monitoring/receiver_monitoring_client_impl.h

receiver/src/monitoring/receiver_monitoring_client_noop.cpp

receiver/src/monitoring/receiver_monitoring_client_noop.h

receiver/unittests/monitoring/receiver_monitoring_mocking.h

receiver/unittests/monitoring/test_monitoring_client.cpp