[Supernova] Distinguish between greenhouse internal and external URLs when parsing urls in alert description

[edda]

In Supernova we parse the alert description for urls that have been added to the description in a specific pattern and turn these into clickable html links with target="_blank". This has been fine for now because the links were always external links to something outside of Supernova. However we now have new alerts that contain deep links into doop. So these are Greenhouse internal links that wouldn't need to open in a new tab.

1. Let's check if we can find a generic way to figure out whether the link is greenhouse internal or not and if internal leave out the target="_blank"
2. Also check if there is a better way to do the parsing stuff so that the output can be a React component instead of plain html. That would make it easier to do something like adding an icon to links that open in a new tab.

[edda]

This might not really make sense. Closing for now until we are more sure what exactly we want to do with links.