add new board members

Author: Mimimi

_data/persons.yml

@@ -1,7 +1,7 @@
-- name: Joël Schulz-Andres
+- name: Jannis Bergmann
   function: "1. Vorsitzender"
   active: true
-  image: "img/persons/joel-schulz-andres.jpg"
+  image: "img/persons/blank.svg"
   order: 0_vorstand_1
   boardmember: true
 
@@ -12,10 +12,10 @@
   order: 0_vorstand_2
   boardmember: true
 
-- name: Mattis Kieffer
-  function: "3. Vorsitzender"
+- name: Scarlet Song
+  function: "3. Vorsitzende"
   active: true
-  image: "img/persons/mattis-kieffer.jpg"
+  image: "img/persons/blank.svg"
   order: 0_vorstand_3
   boardmember: true