remove duplicated strings

app/src/main/res/values-zh-rCN/strings.xml

@@ -2424,8 +2424,6 @@
     <string name="confirm_addons_delete_cache">您确定要删除附加组件元数据缓存文件吗？</string>
     <string name="confirm_addons_delete_cache_yes">确定</string>
     <string name="confirm_addons_delete_cache_no">取消</string>
-    <!-- Content description for headings announced by accessibility service. The first parameter is the text of the heading. Talkback will announce the first parameter and then speak the word "Heading" indicating to the user that this text is a heading for a section. -->
-    <string name="a11y_heading">%s，标题</string>
     <string name="preferences_search_opened_tabs" >搜索已打开的标签页</string>
     <string name="preferences_show_success_download_dialog">完成时的对话框</string>
     <!-- Content description for headings announced by accessibility service. The first parameter is the text of the heading. Talkback will announce the first parameter and then speak the word "Heading" indicating to the user that this text is a heading for a section. -->

app/src/main/res/values-zh-rTW/strings.xml

@@ -2398,8 +2398,6 @@
     <string name="confirm_addons_delete_cache">您確定要刪除附加元件元數據緩存檔案嗎？</string>
     <string name="confirm_addons_delete_cache_yes">確定</string>
     <string name="confirm_addons_delete_cache_no">取消</string>
-    <!-- Content description for headings announced by accessibility service. The first parameter is the text of the heading. Talkback will announce the first parameter and then speak the word "Heading" indicating to the user that this text is a heading for a section. -->
-    <string name="a11y_heading">標題 %s</string>
     <string name="preferences_search_opened_tabs">搜尋已開啟的標籤頁</string>
     <string name="preferences_show_success_download_dialog">完成時的對話方塊</string>
     <!-- Content description for headings announced by accessibility service. The first parameter is the text of the heading. Talkback will announce the first parameter and then speak the word "Heading" indicating to the user that this text is a heading for a section. -->