[feat]: 장바구니 카운트 조회 api 요청 함수작성(#385)

src/services/api/v1/cart.ts

@@ -1,4 +1,4 @@
-import { CartResponse } from 'types/cart';
+import { CartResponse, CartCountResponse } from 'types/cart';
 
 import { apiV1 } from '.';
 
@@ -7,3 +7,9 @@ export const getCartItems = async () => {
 
   return cartItems.data as CartResponse;
 };
+
+export const getCartCount = async () => {
+  const cartCount = await apiV1.get(`/cart/itemCount`);
+
+  return cartCount.data as CartCountResponse;
+};