Make sure we use the pc2 repo

Author: nickygerritsen

icpc-wf/ansible/judgehost.yml

@@ -58,6 +58,8 @@
 
     - name: create chroot
       shell: "{{DJ_DIR}}/misc-tools/dj_make_chroot -y -i openjdk-11-jdk-headless -l \"$(ls /tmp/dj_ansible/install-chroot/*.deb 2>/dev/null | tr '\n' ',')\" 2>&1 | tee /tmp/dj_make_chroot.log"
+      environment:
+        DEBMIRROR: https://pc2cancer.ecs.csus.edu/ubuntu
       args:
         creates: "/chroot/domjudge-systest"