Update doxygen and build documentation on CI
Hi @lrazik,
I extended the CI config to build the Doxygen documentation on the CI. Furthermore, I updated the customizations of the doxygen theme to the latest version of doxygen (1.8.13) and improved the header a bit.
You can download the generated HTML documentation via as an CI artifact: https://git.rwth-aachen.de/acs/core/cim/cimpp/libcimpp/-/jobs/100638/artifacts/download
Cheers