🚨 roles: Fix remaining fqcn linter warnings

fqcn[action-core]: Use FQCN for builtin module actions (service).
    roles/apache_letsencrypt/handlers/main.yml:3 Use `ansible.builtin.service` or `ansible.legacy.service` instead.

    fqcn[action-core]: Use FQCN for builtin module actions (apt).
    roles/dd24_dyndns_cron/tasks/main.yml:2 Use `ansible.builtin.apt` or `ansible.legacy.apt` instead.

    fqcn[action-core]: Use FQCN for builtin module actions (apt).
    roles/desec_dyndns_cron/tasks/main.yml:2 Use `ansible.builtin.apt` or `ansible.legacy.apt` instead.

    fqcn[action-core]: Use FQCN for builtin module actions (command).
    roles/nfs_host/handlers/main.yml:2 Use `ansible.builtin.command` or `ansible.legacy.command` instead.

roles/apache_letsencrypt/handlers/main.yml

@@ -1,6 +1,6 @@
 # Handlers for role apache_letsencrypt
 ---
 - name: Restart apache2
-  service:
+  ansible.builtin.service:
     name: apache2
     state: restarted

roles/dd24_dyndns_cron/tasks/main.yml

@@ -1,6 +1,6 @@
 ---
 - name: Make sure cron and curl are installed
-  apt:
+  ansible.builtin.apt:
     name:
       - cron
       - curl

roles/desec_dyndns_cron/tasks/main.yml

@@ -1,6 +1,6 @@
 ---
 - name: Make sure cron and curl are installed
-  apt:
+  ansible.builtin.apt:
     name:
       - cron
       - curl

roles/nfs_host/handlers/main.yml

@@ -1,3 +1,3 @@
 ---
 - name: Reload nfs
-  command: 'exportfs -ra'
+  ansible.builtin.command: 'exportfs -ra'