Why? Given that the role of Electronic Attack Frigate is to provide support to a gang, the turret/bay slots are great for anti-drone or anti-tackle. A 5m3 Drone bay would also give the Hyena a chance at escape by a successful jam by a EC-300 or a little bit of mitigation with a TD-300. In the event your fleet is low on DPS maybe the extra 10 to 15 dps is always welcomed. The T1 variant of the Hyena has the drone bay, which begs the question why would the T2 not?
Be sure to leave any additional thoughts in the comments!