Revert "fix: error for courses without classroom"

This reverts commit 8c8999b.

lib/l10n/intl_en.arb

@@ -532,7 +532,5 @@
   "start_date_select_message": "You must select the start date of the semester to view your class schedule. Not selecting will result in a date error. \nTip: Start date is the Monday of the first week.",
   "empty_classroom_warning": "Not connected to the campus intranet, so classroom usage information may not be accurate.\nPlease connect to the campus intranet for accurate information.",
   "welcome_prompt":"Welcome to DanXi!\n\nIf you are using DanXi for the first time, perhaps you would like to take a look at the FAQ section?",
-  "sticker": "stickers",
-  "noClassroom": "No classroom",
-  "noCourseId": "No course ID"
+  "sticker": "stickers"
 }

lib/l10n/intl_zh_CN.arb

@@ -524,7 +524,5 @@
   "start_date_select_message": "必须先正确选择学期的开始日期，否则导致日期错误。\n提示：开始日期是第一周的周一。",
   "empty_classroom_warning": "未连接到校园内网，教室使用情况可能不准确。\n请连接到校园内网以获取准确的信息。",
   "welcome_prompt":"欢迎来到旦夕！\n\n如果你是第一次使用旦夕，或许你想看看FAQ板块？",
-  "sticker": "表情",
-  "noClassroom": "无教室",
-  "noCourseId": "无课程编号"
+  "sticker": "表情"
 }

lib/page/subpage_timetable.dart

@@ -450,8 +450,8 @@ class TimetableSubPageState extends PlatformSubpageState<TimetableSubPage> {
                     style: Theme.of(context).textTheme.titleLarge,
                   ),
                   Text((event.course.teacherNames ?? []).join(",")),
-                  Text(event.course.roomName ?? S.of(context).noClassroom),
-                  Text(event.course.courseId ?? S.of(context).noCourseId),
+                  Text(event.course.roomName!),
+                  Text(event.course.courseId!),
                 ],
               )),
               if (event.course.roomId == "999999") ...[