Bump toml11 to 4.4.0, nlohmann_json to 3.12.0

[franzpoeschel]

See also #1839
Updating toml11 and nlohmann_json is needed for CMake 4

[franzpoeschel]

Pybind11 3.0.1 seems to explode MSVC:

  Attributable.cpp
c:\projects\openpmd-api\build\_deps\fetchedpybind11-src\include\pybind11\detail/descr.h(50): fatal error C1202: recursive type or function dependency context too complex [C:\projects\openpmd-api\build\openPMD.py.vcxproj]

It looks like these troubles are caused by Attributable.get_attribute() since that returns a std::variant type of 30~40 options, which Pybind11 is then supposed to convert to a plausible Python value.

I think that the following workaround could fix it, by never exposing the std::variant type to Pybind11:

             "get_attribute",
             [](Attributable &attr, std::string const &key) {
                 auto v = attr.getAttribute(key);
-                return v.getVariant<attribute_types>();
+                return std::visit(
+                    [](auto const &val) { return py::cast(val); },
+                    v.getVariant<attribute_types>());
                 // TODO instead of returning lists, return all arrays (ndim > 0)
                 // as numpy arrays?
             })

[franzpoeschel]

Ok, the above workaround did help, however pybind11 still crashes MSVC:

c:\projects\openpmd-api\build\_deps\fetchedpybind11-src\include\pybind11\pybind11.h(3008): fatal error C1001: An internal error has occurred in the compiler. [C:\projects\openpmd-api\build\openPMD.py.vcxproj]
  (compiler file 'd:\agent\_work\8\s\src\vctools\compiler\utc\src\p2\main.c', line 187)
   To work around this problem, try simplifying or changing the program near the locations listed above.
  Please choose the Technical Support command on the Visual C++ 
   Help menu, or open the Technical Support help file for more information
  Internal Compiler Error in C:\Program Files (x86)\Microsoft Visual

Upgrading toml11 and nlohmann_json is more pressing due to the CMake issues, I will bother with the pybind stuff later.