New comment by sgn on void-packages repository

https://github.com/void-linux/void-packages/pull/31546#issuecomment-863623877

Comment:
+1, with this disallowing, we can move `update-check` out of `xbps-src`, to `common/scripts`.

As of it's now, we need to source the template or do some tricky steps to get current version. If the PR is merged, we can simply `grep ^version=`