Update members.yml

Author: polarvis

_data/people/members.yml

@@ -1,6 +1,6 @@
 # People
 - name: "Alexandra Segerberg"
-  pic: "/assets/images/people/alexandra.jpg"
+  pic: "/assets/images/people/alexandra.png"
   url: "https://www.katalog.uu.se/profile/?id=N18-1556"
   title: "Associate Professor"
   institution: "Uppsala University"