This pr replaces `{{{ }}}` usage by a {{html-safe}} helper. While it doesn't solve the underlying issue, it gives us a path forward without risking breaking too much existing behavior.
Also introduces an htmlSafe computed macro:
```
import { htmlSafe } from "discourse/lib/computed";
htmlDescription: htmlSafe("description")
```
Overtime {{html-safe}} usage should be removed and moved to components properties or specialized components/helpers.
Joffrey JAFFEUX
Robin Ward