Remove pinning c++ version from get_stdopt

[anutosh491]

Description

Please include a summary of changes, motivation and context for this PR.

Fixes #202

Type of change

Please tick all options which are relevant.

• Bug fix
• New feature
• Added/removed dependencies
• Required documentation updates

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.72%. Comparing base (dc14222) to head (2cfa270).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #203   +/-   ##
=======================================
  Coverage   80.72%   80.72%           
=======================================
  Files          19       19           
  Lines         970      970           
  Branches       93       93           
=======================================
  Hits          783      783           
  Misses        187      187           

Files with missing lines	Coverage Δ
src/xinterpreter.cpp	91.20% <ø> (ø)

Files with missing lines	Coverage Δ
src/xinterpreter.cpp	91.20% <ø> (ø)

[anutosh491]

After I updated cppinterop's recipe on emscripten-forge (emscripten-forge/recipes#1515)
we can let Cpp::Evaluate capture the LastValue.

So we don't need to hardcode the version rather, we can run

int __get_cxx_version () {
#if __cplusplus > 202302L
    return 26;
#elif __cplusplus > 202002L
    return 23;
#elif __cplusplus >  201703L
    return 20;
#elif __cplusplus > 201402L
    return 17;
#elif __cplusplus > 201103L || (defined(_WIN32) && _MSC_VER >= 1900)
    return 14;
#elif __cplusplus >= 201103L
   return 11;
#else
  return 0;
#endif
  }
__get_cxx_version ()

In the browser itself and fetch 20. (can be seen if add a simple cout statement in get_stdopt after fetching the version)

auto cxx_version = Cpp::Evaluate(code);
std::cout << std::to_string(cxx_version) << std::endl;
return std::to_string(cxx_version); 

would give the following

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[vgvassilev]

LGTM!

[anutosh491]

Thank you, merging !