message: backend: remove warnings from protobuf-generated files
diff: @@ -18,10 +18,15 @@ target_include_directories(unit_tests_backend
  ${CMAKE_CURRENT_SOURCE_DIR}/../src
  ${CMAKE_CURRENT_SOURCE_DIR}/../src/plugins
  ${PROJECT_SOURCE_DIR}/plugins
  - ${CMAKE_BINARY_DIR}/backend/src
  ${PROJECT_SOURCE_DIR}
  )
  +target_include_directories(unit_tests_backend
  + SYSTEM
  + PRIVATE
  + ${CMAKE_BINARY_DIR}/backend/src
  +)
  +
  target_link_libraries(unit_tests_backend
  backend
  gtest
  