Run jobs directly in STK containers

[jorgepiloto]

It is possible to run a job directly inside a container, see Running jobs in a container. Now that the previous is fixed, I think its feasible migrate to jobs in containers.

The main advantage is the simplification of the many docker exec commands that the pipelines contain. I also wonder if this also has an impact in the performance of CI/CD...

[jorgepiloto]

GitHub actions syntax does not support pre-run commands for containers. Thus, sudo is not available in the containers.