Not unless you want to.
I keep Thrasops which technically have the same venom as dispholidus (boomslangs).
The difference is that the dentitition on the thrasops is different and therefore the delivery system is poopy. I've been tagged and had some localized swelling, itching, bruising and bleeding.
Garters have a decent little venom, but a crappy delivery system. Even if you let the little guy chew on you for a while, you wouldn't be in any danger.