message: Change docfx version from 2.42.4 to 2.42.3
  2.42.4 has problem running under mono
diff: @@ -16,7 +16,7 @@ RUN apt-get update && apt-get install -y \
  # Download DocFX
  WORKDIR /docfx
  -RUN wget https://github.com/dotnet/docfx/releases/download/v2.42.4/docfx.zip -nv
  +RUN wget https://github.com/dotnet/docfx/releases/download/v2.42.3/docfx.zip -nv
  RUN unzip docfx.zip
  WORKDIR /
  