[CI] test all pacxx repositories on cuda

Repositories:

• https://gitlab.dune-project.org/joe/pacxx-docker
• https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx (pacxx!2)
• https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx-runtime (pacxx-runtime!35)
• https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx-samples
• https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx-llvm2 (pacxx-llvm2!6)
• https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx-rv2 (pacxx-rv2!5)
• https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx-clang (pacxx-clang!2)

Replaces: #22 (closed)