message: [CMake]: Fix python command for mingw environment
  In mingw build environment, this fixes the build error:
  'py' is not recognized as an internal or external command
  The 'py' launcher is available for MSVC python only. More
diff: @@ -523,7 +523,7 @@ if(PYTHONINTERP_FOUND AND
  # Skip doing this if the MSVC version is below VS 12.
  # https://cmake.org/cmake/help/latest/variable/MSVC_VERSION.html
  (NOT MSVC OR MSVC_VERSION GREATER 1800))
  - if(WIN32)
  + if(MSVC)
  set(GENERATION_SCRIPT py scripts/generate_code.py)
  else()
  set(GENERATION_SCRIPT scripts/generate_code.py)
  