Add new component: gridss/call

[imsarath]

As part of the distributed computing GRIDSS subworkflow #4498, I added this gridss/call module. This module wraps the variant-calling step: it takes the per-sample preprocessed data and the assembly BAM (along with the input BAM/BAI files and reference genome), calls structural variants across the genome, and produces the final *.sv.gridss.vcf.gz.

PR checklist

Closes #4503

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