message: [vcpkg] remove flushall
diff: @@ -94,7 +94,7 @@ namespace vcpkg::System
  };
  // Flush stdout before launching external process
  - _flushall();
  + fflush(nullptr);
  std::vector<const wchar_t*> env_cstr;
  env_cstr.reserve(env_wstrings.size() + 2);
  @@ -125,7 +125,7 @@ namespace vcpkg::System
  int cmd_execute(const CWStringView cmd_line)
  {
  // Flush stdout before launching external process
  - _flushall();
  + fflush(nullptr);
  // Basically we are wrapping it in quotes
  const std::wstring& actual_cmd_line = Strings::wformat(LR"###("%s")###", cmd_line);
  