Sampling seed interaction with parallel jobs

Setting the sampling seed and n-parallel>1 results in all the parallel jobs using the same sampling seed. If the sampler being used is deterministic, then this will result in the parallel jobs producing identical results.

I don't think this impacts any existing analyses, as they do not set the sampling seed and it is instead set at run time.

Example

See the log files in this directory: https://ldas-jobs.ligo.caltech.edu/~michael.williams/bilby-dev/bilby-pipe/sampling-seed-parallel-jobs/outdir_dynesty_v1.3.0/

Both report:

02:28 bilby_pipe INFO    : Sampling seed set to 1234