update trial time to 2025/06/30

Author: marty5499

public/prod/html/gptbot.html

@@ -64,7 +64,7 @@
     if (!localStorage.getItem("isReadTerm")) {
       parent.Main.popup(
         "歡迎加入！",
-        "您可以免費體驗直到 2024/12/31",
+        "您可以免費體驗直到 2025/06/30",
         "info",
         "知道了",
       ).then(() => {