Deleted non-role playbooks, and fixed up role tasks

roles/debian_update/tasks/apt_upgrade.yaml

@@ -1,5 +1,5 @@
 - name: Full system upgrade
-     become: true
-     ansible.builtin.apt:
-       update_cache: true
-       upgrade:  full
+  become: true
+  ansible.builtin.apt:
+    update_cache: true
+    upgrade:  full

roles/debian_update/tasks/main.yaml

@@ -1 +1,2 @@
-- name: Perform official repository updates               ansible.builtin.import_tasks: apt_upgrade.yaml
+- name: Perform official repository updates
+  ansible.builtin.import_tasks: apt_upgrade.yaml