VCF version 4.1 does not allow source/version in ##INFO fields

Hello,

You are producing invalid VCFs as per https://samtools.github.io/hts-specs/VCFv4.1.pdf

The Source and Version fields were added in VCF 4.2.

This is causing trouble with some of our downstream software that follows the VCF spec very closely.

Have you considered marking your output as VCF 4.2?