Add an opportunity to include URL into the multiple country-specific test lists

[sloncocs]

It would be great to be able to add new URLs to multiple test lists with one contribution.

Right now, if the user wants to add URL to the multiple country-specific test lists (e.g., regionally relevant URLs such as https://arij.net/), the user needs to update 10+ country-specific test lists one by one.

Ideally, it would be great if the same entry could be added to multiple test lists with one update.