New review comment by kawaiiamber on void-packages repository

https://github.com/void-linux/void-packages/pull/27618#discussion_r558836157

Comment:
You hardcoded `2.9.2` in one spot in the URL yet expanded `${version}` in another? It's recommended to expand `${version}` when possible to make maintaining easier. Try switching `distfiles` to `distfiles="https://github.com/sourceryinstitute/OpenCoarrays/archive/${version}.tar.gz"` and match the checksum.