New Github action for C++ Docker project

I am also curious about this too, I hacked something by doing the sonar tasks in a container

i wish I could offload those long tasks to a separate workflow (copying .gc files is not enough, I guess same tools should be installed too and then in an other container this is a bit cumbersome )

BTW I had to use the bw action to download tool (to copy to container),
but I wish i could pull it form container from a pinned version: