New comment by Chocimier on void-packages repository

https://github.com/void-linux/void-packages/pull/34427#issuecomment-989022335

Comment:
- usr should be populated build time (do install), not install time (INSTALL)
- group should be added with dedicated mechanism, not from INSTALL, and should be prefixed with underscore
- use url of specific version (see aur), otherwise template will break continuously
- drop build_style and custom extraction in `do_build`