Replace `prettytable-rs` with another simple table formatter

[tjtelan]

It seems that prettytable-rs has been abandoned and there's a PR for adding it to RustSec Advisory Database.

There are no current reports of CLI issues related to prettytable, so I don't think this is urgent. But since there are a lot of choices for replacements, I think this might come down to personal preferences.

We should balance to keep the table render as close as possible with minimal code changes.

[sehz]

done