feat(docs/meetup-2-guide): add room description link

- Changed the address to be 东上院 instead of 东下院 according to arrangements
- Added room description link

Signed-off-by: Noa Virellia <noa@requiem.garden>

src/content/docs/en/meetup-2-guide.mdx

@@ -12,7 +12,7 @@ Nix CN Meetup #2 is the second Nix-themed gathering in China. We aim to bring to
 ## Event Information
 
 - **Date (UTC+8):** 2025/12/27 (Sat.) ~ 2025/12/28 (Sun.)
-- **Venue:** Dong Xiayuan Building, Minhang Campus, Shanghai Jiao Tong University
+- **Venue:** [101 Dong Shangyuan Building](https://ids.sjtu.edu.cn/build/goRoomPage?param=54870d87298ecd296ef8a0048d8bab4c79eee9f4a5af6afd5ce469bb3834663c9f443d6632843771451540f4171589d4), Minhang Campus, Shanghai Jiao Tong University
   (800 Dongchuan Road, Minhang District, Shanghai)
 
 <LinkButton href='https://v.wjx.cn/vm/m9YRDuN.aspx' icon='external' iconPlacement='end'>

src/content/docs/meetup-2-guide.mdx

@@ -12,7 +12,7 @@ Nix CN Meetup #2 是国内第二次以 Nix 为主题的聚会。我们希望汇
 ## 会议信息
 
 - 日期（UTC +8）：2025/12/27 (Sat.) ~ 2025/12/28 (Sun.)
-- 地点：上海交通大学闵行校区（上海市闵行区东川路800号）东下院
+- 地点：上海交通大学闵行校区（上海市闵行区东川路800号）[东上院 101](https://ids.sjtu.edu.cn/build/goRoomPage?param=54870d87298ecd296ef8a0048d8bab4c79eee9f4a5af6afd5ce469bb3834663c9f443d6632843771451540f4171589d4)
 
 <LinkButton href='https://v.wjx.cn/vm/m9YRDuN.aspx' icon='external' iconPlacement='end'>
     填写报名表