Fix samplesheet channel when `norm` step

[RaqManzano]

Description of the bug

This is a very easy fix, just need to add a new condition after checking meta.status == 0:

else if (meta.sample.contains("vs")) {
                          // Sample already has "vs" format, use as is
                          meta = meta + [id: meta.sample, data_type: 'vcf', variantcaller: variantcaller]
                          return [ meta - meta.subMap('lane'), vcf ]
                           }

This should avoid some weird sample names. Putting it here as it would be good to revise the whole subworkflow in case there is need for some small fix somewhere else related to this.