l10n: alterUrl -> fallbackSshDest (#437)

lib/l10n/app_zh.arb

@@ -11,7 +11,6 @@
   "addr": "地址",
   "all": "所有",
   "alreadyLastDir": "已经是最上层目录了",
-  "alterUrl": "备选链接",
   "askContinue": "{msg}，继续吗？",
   "attention": "注意",
   "authFailTip": "认证失败，请检查密码/密钥/主机/用户等是否错误",
@@ -101,6 +100,7 @@
   "export": "导出",
   "extraArgs": "额外参数",
   "failed": "失败",
+  "fallbackSshDest": "备选 SSH 目标",
   "fdroidReleaseTip": "如果你是从 F-Droid 下载的本应用，推荐关闭此选项",
   "feedback": "反馈",
   "feedbackOnGithub": "如果你有任何问题，请在GitHub反馈",