fix(tasks): include verify_vars.yaml as tasks file

The variable verification was included via include_vars, which is meant for variable files only. Additionally the
first_found lookup had no paths defined, so it searched the files/ subdirectory and the role root instead of tasks/ and
failed with "No file was found". Switching to include_tasks and adding the tasks path makes the verification run at all.

The assertion itself was fully commented out and is now active, so a misconfigured entry fails early instead of being
silently skipped by all four sudoers tasks.

Co-authored-by: Copilot <copilot@github.com>

tasks/main.yaml

@@ -14,13 +14,15 @@
       - vars
 
 - name: Verify variables
-  ansible.builtin.include_vars: "{{ lookup('first_found', params) }}"
+  ansible.builtin.include_tasks: "{{ lookup('first_found', params) }}"
   vars:
     params:
       files:
       - "{{ ansible_facts['distribution'] }}_verify_vars.yaml"
       - "{{ ansible_facts['os_family'] }}_verify_vars.yaml"
-      - "verify_vars.yaml"
+      - verify_vars.yaml
+      paths:
+      - tasks
 
 - name: Install sudo
   ansible.builtin.package: