New review comment by ericonr on void-packages repository

https://github.com/void-linux/void-packages/pull/30738#discussion_r628823420

Comment:
```suggestion
distfiles="${homepage}/releases/download/${version}/polybar-${version}.tar.gz"
```

Neither is very probable, but it's more likely for our package to change name than what upstream uses, so I'd rather keep it typed out explicitly.