Fix the order of variable precedence for Debian OSes.

tasks/main.yml

@@ -1,10 +1,5 @@
 ---
 # Variable setup.
-- name: Set the default PHP version for Debian-based OSes.
-  set_fact:
-    php_default_version_debian: "{{ __php_default_version_debian }}"
-  when: php_default_version_debian is not defined and ansible_os_family == 'Debian'
-
 - name: Include OS-specific variables.
   include_vars: "{{ ansible_os_family }}.yml"
 
@@ -15,6 +10,11 @@
         - "{{ ansible_distribution }}-{{ ansible_distribution_major_version }}.yml"
       skip: true
 
+- name: Set the default PHP version for Debian-based OSes.
+  set_fact:
+    php_default_version_debian: "{{ __php_default_version_debian }}"
+  when: php_default_version_debian is not defined and ansible_os_family == 'Debian'
+
 - name: Define php_packages.
   set_fact:
     php_packages: "{{ __php_packages | list }}"