Run job in apptainer container

[sverhoeven]

It would be nice to run a job for an application inside a apptainer container. On the compute node an apptainer image is required instead of a installed application.

Slurms sbatch has --container argument to specify an OCI container bundle. Investigate if that could be used. Alternatively run subprocess command like apptainer run <image> <command> <args>.

The apptainer image path could be part of the scheduler configuration.

[sverhoeven]

In DIRAC scheduler you can specify apptainer_image path.