* ⚗ add C++17 copies of the test binaries
* ⚗ use proper header for filesystem
* 🚨 fix warnings
* ⚗ do not use too old compilers with C++17
* ✅ add test
* 🔨 add more constraints #3097
* ⚗ use fix from https://github.com/nlohmann/json/pull/3101#issuecomment-998788786
* ⚗ use fix from https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90050
* 👷 use published CI image