networking: Default static_dns to true for static IP configuration

roles/networking/tasks/main.yml

@@ -13,7 +13,7 @@
       copy: src=dns.conf dest={{ chroot_path }}/etc/systemd/network/10-static-ethernet.network.d/dns.conf owner=root group=root mode=0644
       notify:
         - restart networkd
-      when: static_dns|default(false)
+      when: static_dns|default(true)
   when: not dhcp|default(false)
 
 - name: configure network (dhcp)