fix: typo

Author: q1zhen

alumni/alumni.yml

@@ -17,7 +17,7 @@
       favoredLink: github
     - name: 黄京
       image: https://github.com/RadioNoiseE.png
-      bio: UW-Madison '29 Mathematics. Ordinary magician.
+      bio: UW-Madison '30 Mathematics. Ordinary magician.
       links:
         github: https://github.com/RadioNoiseE
         website: https://kekkan.org