Add a filter to only count attempts if a specific profession has been learned

[rdw-software]

Source: Discord

Add option in custom to track a drop, like this https://www.wowhead.com/item=30280/pattern-belt-of-blasting [Binds when picked up] only if char have Tailoring

While this is certainly a niche use case, and currently only useful for custom items (recipes, to be exact), it shouldn't be too difficult to do - at least in theory.