New review comment by Chocimier on void-packages repository

https://github.com/void-linux/void-packages/pull/24117#discussion_r472255708

Comment:
This is checksum of empty string. Empty file is produced because of
```
=> discord-ptb-0.0.21_1: running post_extract ...
/void-packages/srcpkgs/discord-ptb/template: line 21: w3m: command not found
/void-packages/srcpkgs/discord-ptb/template: line 20: curl: command not found
```

Add w3m to hostmakedepends, use `$XBPS_FETCH_CMD -o eula` instead of `curl -L`.