Use group root for /etc/localtime on Linux.

Arch Linux kept changing the group to root, so this change is to avoid unexpected "changed" entries in the ansible diff.

ansible/roles/base/tasks/freebsd.yaml

@@ -1,3 +1,11 @@
+- name: Set timezone
+  file:
+    src: "/usr/share/zoneinfo/{{ timezone|default('UTC') }}"
+    dest: /etc/localtime
+    owner: root
+    group: wheel
+    state: link
+
 - name: Install packages
   package:
     name: