[Solid_software] solid_gemc with apptainer at EL9

[Zhiwen Zhao]

All

As new ifarm9 and farm have moved from EL7 to EL9 and /apps is removed, we need to update instruction to run solid_gemc

solid_gemc itself needs no change to run because it has been based on container for a while, but we need to use 
singularity from apptainer package at /usr/bin/singularity instead from singularity at /apps/singularity/3.9.5
This means there is no need to do "module load", but we need to add shared folder manually by "-B /group:/group -B /u:/u 
-B /w/work:/work -B /w:/w -B /cache:/cache -B /volatile:/volatile -B /lustre:/lustre"

See the updated instruction at https://github.com/JeffersonLab/solid_release/blob/master/howto.md

by the way, as farm9 has no /site either, you want to remove /site/env/syscshrc and /site/env/syslogin in your .cshrc 
and .login to avoid errors.

Zhiwen