Remove database from receiver

receiver/CMakeLists.txt

receiver/src/request_handler/request_factory.h

receiver/src/request_handler/request_handler_db.cpp

receiver/src/request_handler/request_handler_db.h

.../src/request_handler/request_handler_db_check_request.cpp

...er/src/request_handler/request_handler_db_check_request.h

...ver/src/request_handler/request_handler_db_meta_write.cpp

receiver/src/request_handler/request_handler_db_meta_write.h

receiver/src/request_handler/request_handler_db_write.cpp

receiver/src/request_handler/request_handler_db_write.h

receiver/unittests/receiver_mocking.h

receiver/unittests/request_handler/test_request_common.h

...ver/unittests/request_handler/test_request_handler_db.cpp

...request_handler/test_request_handler_db_check_request.cpp

...s/request_handler/test_request_handler_db_meta_writer.cpp

...ttests/request_handler/test_request_handler_db_writer.cpp