[RxCocoa] Gesture Recognizer

• panGesture.rx.event에 옵저버를 추가하는 방식으로 작업한다.

        panGesture.rx.event
            .subscribe(onNext: { [unowned self] gesture in
                guard let target = gesture.view else { return }
                
                let translation = gesture.translation(in: self.view)
                
                target.center.x += translation.x
                target.center.y += translation.y
                
                gesture.setTranslation(.zero, in: self.view)
            })
            .disposed(by: bag)