make sure move responder is set only when gesture is moving vertically with right velocity

Author: William Seow

src/RefreshControl.web.js

@@ -80,6 +80,7 @@ export default function RefreshControl({
         const containerDOM = findNodeHandle(containerRef.current)
         if (!containerDOM) return false
         return containerDOM.children[0].scrollTop === 0
+        && (Math.abs(gestureState.dy) > Math.abs(gestureState.dx) * 2 && Math.abs(gestureState.vy) > Math.abs(gestureState.vx) * 2.5)
       },
       onMoveShouldSetPanResponderCapture: () => false,
       onPanResponderMove: (_, gestureState) => {