instead of crash triggered by map::at std::out_of_range exception.

[MeL] XDMFWriter: Introduce parent data type for meshes with homogeneous and mixed element types

See merge request ogs/ogs!5104

After improvements/fixes the tests will be enabled again

[cmake] Update Boost to 1.82

See merge request ogs/ogs!5122

[doc] Added documentation for OpenMP and debug output

See merge request ogs/ogs!5100

See https://github.com/boostorg/cmake/issues/45#issuecomment-1815570996.

headers are header-only libs, boost are compiled libs.

Uses full sources instead of subset. Download is 90 MB.

[cmake] Use pybind11 with a fix for gcc14.

See merge request ogs/ogs!5119

Wheel create output dir

See merge request ogs/ogs!5118

https://github.com/pybind/pybind11/issues/5206

[cmake] Fixed xdmfdiff-tests not appearing

See merge request ogs/ogs!5115

AddTest() checks for xdmfdiff-target which was added later (after tests have
been processed). Now xdmfdiff-target is created before ProcessLib & co.

[T] Maybe fix mac timeouts.

See merge request ogs/ogs!5117