change no_page_list to no_pages_under_this_page

apps/app/public/static/locales/en_US/translation.json

@@ -168,7 +168,7 @@
     "could_not_creata_path": "Couldn't create path."
   },
   "custom_navigation": {
-    "no_page_list": "There are no pages under this page."
+    "no_pages_under_this_page": "There are no pages under this page."
   },
   "installer": {
     "tab": "Create account",

apps/app/public/static/locales/ja_JP/translation.json

@@ -169,7 +169,7 @@
     "could_not_creata_path": "パスを作成できませんでした。"
   },
   "custom_navigation": {
-    "no_page_list": "このページの配下にはページが存在しません。"
+    "no_pages_under_this_page": "このページの配下にはページが存在しません。"
   },
   "installer": {
     "tab": "アカウント作成",

apps/app/public/static/locales/zh_CN/translation.json

@@ -175,7 +175,7 @@
     "could_not_creata_path": "无法创建路径"
   },
   "custom_navigation": {
-    "no_page_list": "There are no pages under this page."
+    "no_pages_under_this_page": "There are no pages under this page."
   },
 	"installer": {
     "tab": "创建账户",

apps/app/src/components/PageList/PageList.tsx

@@ -51,7 +51,7 @@ const PageList = (props: Props<IPageInfoForEntity>): JSX.Element => {
   if (pageList.length === 0) {
     return (
       <div className="mt-2">
-        <p>{t('custom_navigation.no_page_list')}</p>
+        <p>{t('custom_navigation.no_pages_under_this_page')}</p>
       </div>
     );
   }