Fix menu localization not updated for "Open Tab..." item (#12993)

THe menu item "Open Tab..." was changed to "Open &Tab..." in #12895 but
localization files were not updated. Update it here.

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/lang/menu_zh_cn.utf-8.vim b/runtime/lang/menu_zh_cn.utf-8.vim
index baf56cb..c50fe16 100644
--- a/runtime/lang/menu_zh_cn.utf-8.vim
+++ b/runtime/lang/menu_zh_cn.utf-8.vim
@@ -44,7 +44,7 @@
 " File menuitems {{{1
 menutrans &Open\.\.\.<Tab>:e 打开(&O)\.\.\.<Tab>:e
 menutrans Sp&lit-Open\.\.\.<Tab>:sp 在拆分窗口打开(&L)\.\.\.<Tab>:sp
-menutrans Open\ Tab\.\.\.<Tab>:tabnew 在标签页打开\.\.\.<Tab>:tabnew
+menutrans Open\ &Tab\.\.\.<Tab>:tabnew 在标签页打开\.\.\.<Tab>:tabnew
 menutrans &New<Tab>:enew 新建(&N)<Tab>:enew
 menutrans &Close<Tab>:close 关闭(&C)<Tab>:close
 menutrans &Save<Tab>:w 保存(&S)<Tab>:w