Set the `shared loop devices` Singularity configuration option to `yes`

[dipietrantonio]

This will avoid MPI jobs to consume all the loop devices on a node.

[dipietrantonio]

@ilkhomab @ddeeptimahanti this is another setting we need to have in our Singularity configuration. It was set manually this time, but I believe the best way to have this setting is to modify the recipe to write the setting in the configuration file.