- Can't include a tasks file with a variable in the name, so manually specify

  OpenBSD and Debian cases.

tasks/tls_cert.yml

 ---
 
-- include: 'tls_cert_{{ ansible_os_family }}.yml'
+- include: 'tls_cert_Debian.yml'
+  when: ansible_os_family == 'Debian'
+
+- include: 'tls_cert_OpenBSD.yml'
+  when: ansible_os_family == 'OpenBSD'
 
 - name: Check if dhparams exists and its length
   ignore_errors: yes