Libstellarsolver-dev dependency

[Eric Dejouhanet]

Hello,

There is still a problem with the libstellarsolver-dev dependency in
gitlab CI from PPA indinightly:

> CMake Error at /usr/lib/x86_64-linux-gnu/cmake/StellarSolver/StellarSolverConfig.cmake:89 (message):
>  The imported target "StellarSolver::stellarsolver" references the file
>     "/usr/lib/x86_64-linux-gnu/libstellarsolver.so.1.5"
>  but this file does not exist.  Possible reasons include:
>  * The file was deleted, renamed, or moved to another location.
>  * An install or uninstall procedure did not complete successfully.
>  * The installation package was faulty and contained
>     "/usr/lib/x86_64-linux-gnu/cmake/StellarSolver/StellarSolverConfig.cmake"
>  but not all the files it references.
> Call Stack (most recent call first):
>  CMakeLists.txt:212 (find_package)
> -- Configuring incomplete, errors occurred!

Would it be possible to take care of this to allow proper verification
of MRs and master commits?

-- 
-- eric.dejouhanet at gmail.com - https://astronomy.dejouha.net