chore: migrate bare ansible_* facts to ansible_facts[] syntax

tasks/main.yaml

@@ -2,12 +2,12 @@
 
 # load variables and collect version information
 - name: "include vars and collect versions"
-  when: "ansible_os_family not in 'Alpine'"
+  when: "ansible_facts['os_family'] not in 'Alpine'"
   block:
 
     # load os specific variables
     - name: "include os specific vars"
-      ansible.builtin.include_vars: "{{ ansible_os_family }}.yaml"
+      ansible.builtin.include_vars: "{{ ansible_facts['os_family'] }}.yaml"
 
     # collect zabbix-agent2 version information
     - name: "collect version information"
@@ -22,4 +22,4 @@
 # zabbix-agent prerequisites
 - name: "zabbix-agent prerequisites"
   ansible.builtin.import_tasks: "prerequisites.yaml"
-  when: "ansible_os_family not in 'Alpine'"
+  when: "ansible_facts['os_family'] not in 'Alpine'"