turn:bus:lanes (special turn rules for buses)

https://wiki.openstreetmap.org/wiki/Key:turn:bus:lanes

It is kind of weird and may be and unique to Kraków, but here bus lanes are often constructed from stretches of

- only for special vehicles (buses, taxi, motorcycles, police and ambulances in nonemergency mode etc)
- for anyone turning right, and for all that special vehicles for turning right or going straight

See for example https://www.openstreetmap.org/way/217209131 `turn:lanes=||right` `turn:bus:lanes=||through;right`

Not sure is it ridiculous to implement or something along "feel free to make a PR"

Right now it is used just 73 times across entire Earth, but ignoring it in Kraków would result in a noticeable worse bus behavior (though it is kind of ridiculous, feel free to WONTFIX it)