Updates to slurm backend
Depends on changes to CP3SlurmUtils: to be merged when https://cp3-git.irmp.ucl.ac.be/cp3-support/CP3SlurmUtils/-/merge_requests/4 is merged (and ideally when the new version appears on testpypi).
- Some CP3SlurmUtils options changed name
- Environment config file (.ini): do not convert content to lowercase when reading, since options propagated to CP3SlurmUtils (which is case-sensitive) would not be recognized (unless they had a default value hardcoded in bamboo).
- Slurm options read from the config file: try to match the type (int/bool) expected by CP3SlurmUtils