Two changes are needed to be compatible with KNewStuff > 5.62:
- the installItem call now requires two arguments (previously this with
  only the first)
- binding the items model to the engine property does not work anymore
  but binding it directly to the engine object solves the issue

Note that this is a runtime only issue because QML methods are used.
However, this patch increases the minimal required version to 5.63 for
all frameworks, which shall help to ensure a functional KNewStuff
version being present.

BUG: 414985