Filter course sessions by campus

Currently, class sessions in international campuses (Croatia, Dubai, etc) are treated the same as Rochester sessions, and are enabled by default. It is possible to filter them out by hand, but it'd be better to have an integrated campus filter. Rochester sessions have a two digit session number (eg ABCD-101-01), while international sessions have a three-digit number (ABCD-101-X01), where X is 5 for Croatia or 6 for Dubai (other numbers may exist).

未指定任何文件或测试。首先定位当前手动筛选会话的行为，以及解释会话编号的代码；使用 Rochester 的两位数字格式和国际三位数字示例作为要追踪的案例。完成的标准是，用户可以在应用程序中筛选校区会话，包括 Croatia 和 Dubai 的会话，而不会默认将它们视为 Rochester 会话。

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