New review comment by ahesford on void-packages repository

https://github.com/void-linux/void-packages/pull/27431#discussion_r549737236

Comment:
Why make this change? There is no need to break the build if this file disappears. Also, while you're editing this line, might as well make it
```bash
rm -f ${DESTDIR}/${py3_sitelib}/dkim/__main__.py
```