Upgrate gnu to version 11 or 12
Now that DYNAMICO builds with FCM2 we can use Fortran SUBMODULEs. For gfortran this requires version 11 or 12. Thus an upgrade of the GNU-based images is required.
I have a brute-force 'upgrade' of the Dockerfiles to do this here : https://gitlab.in2p3.fr/thomas.dubos/dockerimages/-/tree/feature/gnu-11 However it breaks many things in the GNU image and must not be imported as is.
If we redo the GNU image it is the right moment to ask if we want to keep it based on SPACK. The rationale was to have full control of the details of the MPI library and be able to run DYNAMICO in this image with good performance. I think this goal is not a current goal now. It should be possible to simplify a lot the Dockerfiles by basing the GNU image on a recent Ubuntu and aligning the Dockerfiles as much as possible.
Or, maybe, it is simpler to keep the Dockerfile mostly untouched and just ask SPACK for a recent gfortran.