gitlab-ci: always run the containers build

gitlab-ci: always run the containers build

If the first time a fork was created, the job creating the containers was
manually cancelled, this would have left the fork unable to use the CI
(until the next automatic regeneration of the container).

Avoid this by always running the container-generation job, even though
99% of the time it will spin up, see that the container exists and shut
down.

Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>