Support C++23

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When we set CXX_standards as 23, hunter raise this error
[hunter ** INTERNAL **] CXX standard 23 not known
I wonder expected CXX_standard is set in below, we should just add 23?
hunter/cmake/modules/hunter_get_lang_standard_flag.cmake

function(hunter_get_lang_standard_flag LANG OUTPUT)
  # https://github.com/Kitware/CMake/blob/9d48d3f61b25400a191f12ea92b8e5496ab47a8f/Source/cmLocalGenerator.cxx#L1766-L1782
  set(CXX_standards 20 17 14 11 98)
  set(C_standards 11 99 90)

it has a comment pointing to a specific version of CMake but not sure where the version is from.