Discover string freeze exception for 6.6

Hi!

We have been doing small fixes to Discover rating system, but we need
to rename one item in the sort button for it to make sense.

In this case, we're changing word "Rating" to "Popularity"

https://invent.kde.org/plasma/discover/-/merge_requests/1232#note_1411162

There are no other translation related changes.

Would this be okay for 6.6 release?

(When answering **please use reply-all** since i have not subscribed to this list)


Thanks!
- Akseli Lahtinen