fix spelling

packages/app/test/integration/service/v5.non-public-page.test.ts

@@ -605,7 +605,7 @@ describe('PageService page operations with non-public pages', () => {
 
       return duplicatedPage;
     };
-    test('Duplicate sinle page with GRANT_RESTRICTED', async() => {
+    test('Duplicate single page with GRANT_RESTRICTED', async() => {
       const basePage = await Page.findOne({ path: '/np_duplicate1' }).populate({ path: 'revision', model: 'Revision' });
       const baseRevision = basePage.revision;
       expectAllToBeTruthy([basePage, baseRevision]);