Picongpu: tbg: environment before submit

[ax3l]

First seen at NERSC: It's more efficient to prepare module and environment loading already on the head node instead of doing so in the first compute node of a job.

Potentially a workflow that should be covered by tbg, e.g. in its submitAction.sh.

[psychocoderHPC]

On slurm systems in general there is no need to load the environment systems again because slurm is storing loaded modules during sbatch.
We need to take care because slurm is not remembering all envirobment variables like the author for PIConGPU we set in our profile.

[ax3l]

Sounds good, so basically we can just simplify the profile template then to not load all modules on startup, and keep the simple bash variables such as author baked it.