sbatch not working if SlurmdSpoolDir is undefined

[jakob1379]

If I do not define SlurmdSpoolDir I get the following error when running any type of jobs

slurmstepd-node-1: error: execve(): /var/lib/slurm/slurmctld/job00218/slurm_script: Permission denied

But if I set SlurmdSpoolDir to just the default SlurmdSpoolDir: "/var/spool/slurmd" i can successfully dispatch jobs. This seems like a slurm issue, but for the sake of usability I suggest simply adding the default value to the slurm.conf if undefined.

[jakob1379]

If need be I'd gladly make the PR