Python bindings build fail on Ubuntu 24.04

[boxanm]

This is a preliminary issue that needs to be resolved before we add support for Ubuntu 24.

Libpointmatcher relies on pybind 2.5.0, which was released over 4 years ago. In Ubuntu 24, this dependency started to break. There are two issues I have encountered so far:

1. pybind 2.5.0 depends on distutils, which was marked deprecated in Python3.10 and was removed in Python3.12 that comes with Ubuntu 24.
2. After installing the dependency manually (it is part of setuptools), building pybind 2.5.0 fails in multiple places; see some examples below

   /libraries/pybind11/include/pybind11/cast.h: In function 'std::string pybind11::detail::error_string()':
   /libraries/pybind11/include/pybind11/cast.h:446:36: error: invalid use of incomplete type 'PyFrameObject' {aka 'struct _frame'}
   446 |                 "  " + handle(frame->f_code->co_filename).cast<std::string>() +
     |                                    ^~
   /libraries/pybind11/include/pybind11/cast.h:446:75: error: expected primary-expression before '>' token
   446 |                 "  " + handle(frame->f_code->co_filename).cast<std::string>() +
     |                                                                           ^

   Overall, I think now would be a good time to investigate and migrate to newer releases of pybind.