I can only find English translations online. The wiki page says an early appearance of the bull was in 'Expugnatio Hibernica' (1189) but I can only find English translations of this too.
The Latin text of the Expugnatio, along with a discussion of the manuscripts from which it is derived, is in the public domain here. As far as I can tell, there as been no more recent scholarly edition in any of the usual places.