minor fix of typo

src/module/alertModal.js

@@ -21,6 +21,7 @@ const customClass = {
  */
 export async function saveFilter(addFilterId) {
   let fileName = '';
+  const pageAdminStore = PageAdminStore();
 
   const { value, isConfirmed } = await Swal.fire({
     title: 'SAVE NEW FILTER',
@@ -55,7 +56,7 @@ export async function saveFilter(addFilterId) {
     return true;
   } else { // 點擊取消或空白處，為存檔失敗。
     // console.log("PageAdminStore.activePage", PageAdminStore.activePage);
-    PageAdminStore.keepPreviousPage();
+    pageAdminStore.keepPreviousPage();
     return false;
   }
 }