Add a missing Chinese translation line

lang/简体中文.json

@@ -108,6 +108,7 @@
                 "show": "掉宝活动:",
                 "linked": "仅已关联账户的游戏掉宝",
                 "expired": "已结束",
+                "excluded": "未添加的掉宝活动",
                 "upcoming": "即将上线",
                 "finished": "已完成",
                 "refresh": "刷新"