[hooks] 확장자 수정 및 hook 추가

Detail Notes :

1. usePriceInfo 확장자 수정, jsx → js
2. useScrollTo 추가

com.twin.app.shoptime/src/hooks/useScrollTo.js

@@ -0,0 +1,21 @@
+import React, { useCallback, useEffect, useRef } from "react";
+
+export default function useScrollTo() {
+  const scrollTo = useRef();
+
+  const scrollTop = useCallback(() => {
+    if (scrollTo && scrollTo.current) {
+      scrollTo.current({ position: { y: 0 }, animate: true });
+    }
+  }, []);
+
+  const getScrollTo = useCallback((cbScrollTo) => {
+    scrollTo.current = cbScrollTo;
+  }, []);
+
+  useEffect(() => {
+    scrollTop();
+  }, []);
+
+  return { getScrollTo, scrollTop };
+}