archusers: Make foxboron a dev

After the promotion of foxboron to dev, we have changed his role on archusers and ran the playbook against the machines. Closes #440 (closed)

group_vars/all/archusers.yml

@@ -257,6 +257,7 @@ arch_users:
     name: "Morten Linderud"
     ssh_key: foxboron.pub
     groups:
+      - dev
       - tu
   foxxx0:
     name: "Thore Bödecker"