tardis should attempt to check for slurm max array size config before adopting a default

[afmcc]

tardis uses max array size of 500 and creates multiple array jobs as required for job arrays > 500.
However this will result in incorrect behaviour if max array size happened to be < 500
(only some of the array would be processed).
we can
scontrol show config | grep MaxArraySize
MaxArraySize = 10000