nits

Author: yizhuoliang

_data/team.yml

@@ -244,7 +244,7 @@ current-students:
 
   - name: <a href="https://yizhuoliang.github.io/">Yizhuo Liang (Coulson)</a>
     lastname: Liang
-    photo: Coulson/coulson.jpg
+    photo: Coulson/coulson.png
     info: PhD Student
     advisor:
       - Seo Jin Park