message: Fix macos ci build with OpenCV 3
diff: @@ -29,6 +29,7 @@ elif [[ "$OS_FAMILY" == "osx" ]]; then
  # export DYLD_LIBRARY_PATH="$toolchain_path/usr/lib/"
  if [[ "$BREW_OPENCV_VERSION" != "" ]]; then # brew build
  if [[ "$BREW_OPENCV_VERSION" == "@3" ]]; then
  + export CMAKE_PREFIX_PATH="/usr/local/Cellar/opencv3@/3.4.10_2"
  export PKG_CONFIG_PATH="/usr/local/opt/opencv@3/lib/pkgconfig"
  fi
  else # framework build
  